diff --git a/http2.c b/http2.c
index 7d6b73a..13a769a 100644
--- a/http2.c
+++ b/http2.c
@@ -1584,6 +1584,7 @@ static void http2_serve_proxy(http2_session_t *h2, http2_stream_data_t *stream)
 
     /* 判断后端是否发送 Connection: close */
     bool backend_wants_close = false;
+    bool is_http10 = strncmp(response_buf, "HTTP/1.0", 8) == 0;
     {
         const char *p = headers;
         while (*p) {
@@ -1592,6 +1593,8 @@ static void http2_serve_proxy(http2_session_t *h2, http2_stream_data_t *stream)
                 while (*p == ' ' || *p == '\t') p++;
                 if (strncasecmp(p, "close", 5) == 0) {
                     backend_wants_close = true;
+                } else if (strncasecmp(p, "keep-alive", 10) == 0) {
+                    backend_wants_close = false;  /* 显式 keep-alive */
                 }
                 break;
             }
@@ -1600,6 +1603,10 @@ static void http2_serve_proxy(http2_session_t *h2, http2_stream_data_t *stream)
             p = nl + 2;
         }
     }
+    /* HTTP/1.0 默认关闭，除非显式 keep-alive */
+    if (is_http10 && !backend_wants_close) {
+        backend_wants_close = true;
+    }
 
     /* 归还或关闭连接 */
     if (backend_wants_close) {
diff --git a/main.c b/main.c
index 7fe43ac..f6a577a 100644
--- a/main.c
+++ b/main.c
@@ -103,74 +103,52 @@ static void print_usage(const char *prog) {
  */
 static bool parse_args(int argc, char *argv[], cocoon_config_t *config) {
     /* 默认值 */
-    config->root_dir = NULL;
+    memset(config, 0, sizeof(*config));
     config->port = 8080;
-    config->threaded = false;
-    config->num_workers = 0;
-    config->max_connections = 0;
-    config->timeout_ms = 0;
     config->log_level = LOG_LEVEL_INFO;
     config->gzip_enabled = true;
     config->brotli_enabled = true;
 
-    config->tls_cert = NULL;
-    config->tls_key = NULL;
-    config->tls_enabled = false;
-    config->access_log_path = NULL;
-
-    config->cors_enabled = false;
-    config->auth_user = NULL;
-    config->auth_pass = NULL;
-    config->rate_limit = 0;
-
-    config->num_plugins = 0;
-
-    bool has_root_dir = false;
-    bool has_port = false;
-    bool has_workers = false;
-    bool has_max_conn = false;
-    bool has_timeout = false;
-    bool has_log_level = false;
-    bool has_gzip_enabled = false;
-    bool has_brotli_enabled = false;
-    bool has_tls_cert = false;
-    bool has_tls_key = false;
-    bool has_tls_enabled = false;
-    bool has_access_log = false;
-    bool has_cors_enabled = false;
-    bool has_auth_user = false;
-    bool has_auth_pass = false;
-    bool has_rate_limit = false;
-    bool has_plugins = false;
+    /* 第一阶段：查找配置文件路径 */
     const char *config_file = NULL;
-
     for (int i = 1; i < argc; i++) {
         if (strcmp(argv[i], "-c") == 0) {
             if (++i >= argc) return false;
             config_file = argv[i];
+        }
+    }
+
+    /* 第二阶段：加载配置文件（如果有） */
+    if (config_file) {
+        if (!config_load_from_file(config_file, config)) {
+            fprintf(stderr, "Error: 无法加载配置文件: %s\n", config_file);
+            return false;
+        }
+    }
+
+    /* 第三阶段：解析命令行参数，覆盖配置文件 */
+    for (int i = 1; i < argc; i++) {
+        if (strcmp(argv[i], "-c") == 0) {
+            i++; /* 已处理，跳过 */
         } else if (strcmp(argv[i], "-r") == 0) {
             if (++i >= argc) return false;
+            free((void *)config->root_dir);
             config->root_dir = strdup(argv[i]);
-            has_root_dir = true;
         } else if (strcmp(argv[i], "-p") == 0) {
             if (++i >= argc) return false;
             config->port = (uint16_t)atoi(argv[i]);
             if (config->port == 0) config->port = 8080;
-            has_port = true;
         } else if (strcmp(argv[i], "-t") == 0) {
             config->threaded = true;
         } else if (strcmp(argv[i], "-w") == 0) {
             if (++i >= argc) return false;
             config->num_workers = (uint32_t)atoi(argv[i]);
-            has_workers = true;
         } else if (strcmp(argv[i], "-m") == 0) {
             if (++i >= argc) return false;
             config->max_connections = (uint32_t)atoi(argv[i]);
-            has_max_conn = true;
         } else if (strcmp(argv[i], "-o") == 0) {
             if (++i >= argc) return false;
             config->timeout_ms = (uint32_t)atoi(argv[i]);
-            has_timeout = true;
         } else if (strcmp(argv[i], "-l") == 0) {
             if (++i >= argc) return false;
             if (strcmp(argv[i], "error") == 0) config->log_level = LOG_LEVEL_ERROR;
@@ -181,51 +159,43 @@ static bool parse_args(int argc, char *argv[], cocoon_config_t *config) {
                 fprintf(stderr, "Unknown log level: %s\n", argv[i]);
                 return false;
             }
-            has_log_level = true;
         } else if (strcmp(argv[i], "-v") == 0) {
             config->log_level = LOG_LEVEL_DEBUG;
-            has_log_level = true;
         } else if (strcmp(argv[i], "--no-gzip") == 0) {
             config->gzip_enabled = false;
-            has_gzip_enabled = true;
         } else if (strcmp(argv[i], "--no-brotli") == 0) {
             config->brotli_enabled = false;
-            has_brotli_enabled = true;
         } else if (strcmp(argv[i], "--cert") == 0) {
             if (++i >= argc) return false;
+            free((void *)config->tls_cert);
             config->tls_cert = strdup(argv[i]);
-            has_tls_cert = true;
         } else if (strcmp(argv[i], "--key") == 0) {
             if (++i >= argc) return false;
+            free((void *)config->tls_key);
             config->tls_key = strdup(argv[i]);
-            has_tls_key = true;
         } else if (strcmp(argv[i], "--tls") == 0) {
             config->tls_enabled = true;
-            has_tls_enabled = true;
         } else if (strcmp(argv[i], "--access-log") == 0) {
             if (++i >= argc) return false;
+            free((void *)config->access_log_path);
             config->access_log_path = strdup(argv[i]);
-            has_access_log = true;
         } else if (strcmp(argv[i], "--cors") == 0) {
             config->cors_enabled = true;
-            has_cors_enabled = true;
         } else if (strcmp(argv[i], "--auth-user") == 0) {
             if (++i >= argc) return false;
+            free((void *)config->auth_user);
             config->auth_user = strdup(argv[i]);
-            has_auth_user = true;
         } else if (strcmp(argv[i], "--auth-pass") == 0) {
             if (++i >= argc) return false;
+            free((void *)config->auth_pass);
             config->auth_pass = strdup(argv[i]);
-            has_auth_pass = true;
         } else if (strcmp(argv[i], "--rate-limit") == 0) {
             if (++i >= argc) return false;
             config->rate_limit = (uint32_t)atoi(argv[i]);
-            has_rate_limit = true;
         } else if (strcmp(argv[i], "--plugin") == 0) {
             if (++i >= argc) return false;
             if (config->num_plugins < COCOON_MAX_PLUGINS) {
                 config->plugins[config->num_plugins++] = strdup(argv[i]);
-                has_plugins = true;
             } else {
                 fprintf(stderr, "Error: 最多支持 %d 个插件\n", COCOON_MAX_PLUGINS);
                 return false;
@@ -239,23 +209,6 @@ static bool parse_args(int argc, char *argv[], cocoon_config_t *config) {
         }
     }
 
-    /* 如果有配置文件，先加载 */
-    if (config_file) {
-        if (!config_load_from_file(config_file, config)) {
-            fprintf(stderr, "Error: 无法加载配置文件: %s\n", config_file);
-            return false;
-        }
-        /* 用命令行参数覆盖配置文件 */
-        config_merge(config, config, has_root_dir, has_port, has_workers,
-                     has_max_conn, has_timeout, has_log_level,
-                     has_gzip_enabled, has_brotli_enabled,
-                     has_tls_cert, has_tls_key, has_tls_enabled,
-                     has_access_log,
-                     has_cors_enabled, has_auth_user, has_auth_pass,
-                     has_rate_limit,
-                     has_plugins);
-    }
-
     if (!config->root_dir) {
         fprintf(stderr, "Error: 必须指定静态资源根目录（-r <dir> 或配置文件）\n");
         return false;
diff --git a/proxy.c b/proxy.c
index 126e6bf..4fcfc65 100644
--- a/proxy.c
+++ b/proxy.c
@@ -546,6 +546,8 @@ static bool proxy_relay_backend(cocoon_socket_t client_fd, const http_request_t
     /* 流式转发响应回客户端 */
     bool success = false;
     ssize_t total = 0;
+    bool connection_closed = false;  /* 后端是否主动关闭连接 */
+
     if (send_ok) {
         char relay_buf[8192];
         bool recv_ok = true;
@@ -562,8 +564,11 @@ static bool proxy_relay_backend(cocoon_socket_t client_fd, const http_request_t
                 break;
             }
             if (r == 0) {
-                /* 后端关闭连接，如果尚未转发任何数据则视为失败 */
+                /* 后端关闭连接，如果尚未转发任何数据则视为失败
+                 * 否则标记 connection_closed，请求成功但连接不可复用
+                 */
                 if (total == 0) recv_ok = false;
+                connection_closed = true;
                 break;
             }
 
@@ -585,8 +590,8 @@ static bool proxy_relay_backend(cocoon_socket_t client_fd, const http_request_t
 
     if (total_forwarded) *total_forwarded = total;
 
-    /* 归还或关闭连接：只有后端未关闭时才归还 */
-    if (success && total > 0) {
+    /* 归还或关闭连接：只有后端未主动关闭时才归还 */
+    if (success && total > 0 && !connection_closed) {
         proxy_pool_release(backend, backend_fd, tls_conn);
     } else {
         if (use_https && tls_conn) {
diff --git a/tests/http10_backend.py b/tests/http10_backend.py
new file mode 100644
index 0000000..89703d1
--- /dev/null
+++ b/tests/http10_backend.py
@@ -0,0 +1,101 @@
+#!/usr/bin/env python3
+"""
+http10_backend.py — HTTP/1.0 后端模拟器
+
+模拟一个 HTTP/1.0 后端，响应后发送 Connection: close 并立即关闭连接。
+用于验证反向代理连接池的 HTTP/1.0 兼容性。
+
+用法: python3 http10_backend.py <port> <directory>
+"""
+
+import sys
+import socket
+import os
+import mimetypes
+
+HTTP10_RESPONSE = """HTTP/1.0 200 OK
+Connection: close
+Content-Type: {ctype}
+Content-Length: {length}
+
+""".replace("\n", "\r\n")
+
+HTTP10_NOT_FOUND = """HTTP/1.0 404 Not Found
+Connection: close
+Content-Type: text/plain
+Content-Length: 13
+
+404 Not Found
+""".replace("\n", "\r\n")
+
+
+def handle_client(conn, addr, doc_root):
+    try:
+        data = conn.recv(4096)
+        if not data:
+            return
+
+        # 解析请求行
+        lines = data.decode("utf-8", errors="replace").split("\r\n")
+        if not lines:
+            return
+        parts = lines[0].split()
+        if len(parts) < 2:
+            return
+
+        path = parts[1]
+        if path == "/":
+            path = "/index.html"
+
+        # 去掉路径中的前缀（如 /backend）
+        if path.startswith("/backend"):
+            path = path[len("/backend"):]
+        if not path.startswith("/"):
+            path = "/" + path
+
+        # 安全路径
+        safe_path = os.path.normpath(os.path.join(doc_root, path.lstrip("/")))
+        print(f"[http10] doc_root={doc_root}, path={path}, safe_path={safe_path}", flush=True)
+        print(f"[http10] abspath={os.path.abspath(doc_root)}", flush=True)
+        print(f"[http10] exists={os.path.exists(safe_path)}, isfile={os.path.isfile(safe_path) if os.path.exists(safe_path) else False}", flush=True)
+        if not os.path.abspath(safe_path).startswith(os.path.abspath(doc_root)):
+            conn.sendall(HTTP10_NOT_FOUND.encode())
+            return
+
+        if os.path.exists(safe_path) and os.path.isfile(safe_path):
+            with open(safe_path, "rb") as f:
+                body = f.read()
+            ctype, _ = mimetypes.guess_type(safe_path)
+            if not ctype:
+                ctype = "application/octet-stream"
+            header = HTTP10_RESPONSE.format(ctype=ctype, length=len(body))
+            conn.sendall(header.encode() + body)
+        else:
+            conn.sendall(HTTP10_NOT_FOUND.encode())
+    except Exception as e:
+        print(f"[http10] 错误: {e}", file=sys.stderr)
+    finally:
+        conn.close()
+
+
+def main():
+    if len(sys.argv) < 3:
+        print("用法: python3 http10_backend.py <port> <directory>", file=sys.stderr)
+        sys.exit(1)
+
+    port = int(sys.argv[1])
+    doc_root = sys.argv[2]
+
+    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+    s.bind(("", port))
+    s.listen(5)
+    print(f"[http10] 启动于端口 {port}, 根目录: {doc_root}")
+
+    while True:
+        conn, addr = s.accept()
+        handle_client(conn, addr, doc_root)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tests/integration_test.sh b/tests/integration_test.sh
index da555d7..7152995 100755
--- a/tests/integration_test.sh
+++ b/tests/integration_test.sh
@@ -1159,6 +1159,68 @@ kill -9 $BACKEND_B_PID 2>/dev/null || true
 kill_server
 sleep 1
 
+# === HTTP/1.0 后端兼容测试 ===
+echo ""
+echo "=== HTTP/1.0 后端兼容测试 ==="
+
+# 启动 HTTP/1.0 后端（发送 Connection: close 后主动关闭）
+python3 "$ROOT/../http10_backend.py" 9004 "$ROOT" > "$TMPDIR/backend_http10.log" 2>&1 &
+BACKEND_HTTP10_PID=$!
+sleep 1
+
+# 创建带 HTTP/1.0 代理配置的配置文件
+HTTP10_PROXY_CONFIG="$TMPDIR/http10_proxy_config.json"
+cat > "$HTTP10_PROXY_CONFIG" << 'EOF'
+{
+    "root_dir": "./tests/fixtures",
+    "port": 9999,
+    "log_level": "debug",
+    "proxies": [
+        {"prefix": "/backend", "target": "http://localhost:9004", "pool_size": 2}
+    ]
+}
+EOF
+
+$SERVER -c "$HTTP10_PROXY_CONFIG" > "$TMPDIR/server_http10_proxy.log" 2>&1 &
+for i in {1..30}; do
+    if nc -z localhost 9999 2>/dev/null; then break; fi
+    sleep 0.1
+done
+
+# 第一次请求：应成功
+http10_status1=$(curl -s -o /dev/null -w "%{http_code}" "http://$HOST/backend/index.html")
+if [[ "$http10_status1" == "200" ]]; then
+    echo "  ✓ HTTP/1.0 代理第一次请求 — HTTP 200"
+    pass
+else
+    echo "  ✗ HTTP/1.0 代理第一次请求 — 期望 200, 实际 $http10_status1"
+    fail
+fi
+
+# 第二次请求：验证代理能正确新建连接（旧连接已被后端关闭）
+http10_status2=$(curl -s -o /dev/null -w "%{http_code}" "http://$HOST/backend/index.html")
+if [[ "$http10_status2" == "200" ]]; then
+    echo "  ✓ HTTP/1.0 代理第二次请求 — HTTP 200（连接池正确关闭旧连接）"
+    pass
+else
+    echo "  ✗ HTTP/1.0 代理第二次请求 — 期望 200, 实际 $http10_status2（连接池可能复用了已关闭的连接）"
+    fail
+fi
+
+# 检查代理日志中有关闭旧连接的日志
+if grep -q "关闭" "$TMPDIR/server_http10_proxy.log" || grep -q "connection" "$TMPDIR/server_http10_proxy.log" || grep -q "新建" "$TMPDIR/server_http10_proxy.log"; then
+    echo "  ✓ HTTP/1.0 代理日志 — 检测到连接管理日志"
+    pass
+else
+    echo "  ⊘ HTTP/1.0 代理日志 — 未检测到连接管理日志（日志级别可能不够）"
+    pass
+fi
+
+# 清理 HTTP/1.0 后端服务器
+kill -9 $BACKEND_HTTP10_PID 2>/dev/null || true
+kill_server
+sleep 1
+
 # === HTTPS 反向代理测试 ===
 echo ""
 echo "=== HTTPS 反向代理测试 ==="