diff --git a/.env.example b/.env.example
index 86fe96c..62f6d69 100644
--- a/.env.example
+++ b/.env.example
@@ -4,21 +4,17 @@
 ############
 # 运行时配置
 ############
-SOCIAL_RUNTIME__ENVIRONMENT=dev          # dev / prod (DEPRECATED: use SOCIAL_WEB__SERVER)
+SOCIAL_RUNTIME__ENVIRONMENT=dev
 SOCIAL_RUNTIME__DEBUG=true
 SOCIAL_RUNTIME__LOG_LEVEL=INFO
 SOCIAL_RUNTIME__SQL_LOG_QUERIES=false
 
 ############
-# Web 服务器配置（显式参数控制）
+# Web 服务器配置（Uvicorn）
 ############
 SOCIAL_WEB__HOST=0.0.0.0
 SOCIAL_WEB__PORT=5775
-SOCIAL_WEB__RELOAD=false
-SOCIAL_WEB__GUNICORN__WORKERS=2
-SOCIAL_WEB__GUNICORN__WORKER_CLASS=uvicorn.workers.UvicornWorker
-SOCIAL_WEB__GUNICORN__TIMEOUT=30
-SOCIAL_WEB__GUNICORN__KEEPALIVE=2
+SOCIAL_WEB__WORKERS=2
 
 ############
 # Redis 配置
diff --git a/backend/Dockerfile b/backend/Dockerfile
index f845494..c3d901b 100644
--- a/backend/Dockerfile
+++ b/backend/Dockerfile
@@ -12,4 +12,4 @@ COPY backend/alembic ./backend/alembic
 
 ENV PYTHONPATH=/app/backend/src
 
-CMD ["uv", "run", "gunicorn", "backend.src.app:app", "--bind", "0.0.0.0:8000", "--workers", "2"]
+CMD ["uv", "run", "uvicorn", "app:app", "--host", "0.0.0.0", "--port", "8000", "--workers", "2"]
diff --git a/backend/src/core/config/settings.py b/backend/src/core/config/settings.py
index 1138513..4e5d016 100644
--- a/backend/src/core/config/settings.py
+++ b/backend/src/core/config/settings.py
@@ -8,6 +8,23 @@ from pydantic import BaseModel, Field, computed_field, field_validator, model_va
 from pydantic_settings import BaseSettings, SettingsConfigDict
 
 
+def _resolve_project_root() -> Path:
+    current = Path(__file__).resolve()
+    for parent in current.parents:
+        if (
+            (parent / "pyproject.toml").is_file()
+            and (parent / "backend").is_dir()
+            and (parent / "infra").is_dir()
+        ):
+            return parent
+
+    for parent in current.parents:
+        if parent.name == "backend":
+            return parent.parent
+
+    return Path.cwd().resolve()
+
+
 class RuntimeSettings(BaseModel):
     environment: Literal["dev", "test", "prod"] = "dev"
     service_name: str = "app"
@@ -171,6 +188,9 @@ def _resolve_env_file() -> str:
     return ".env"
 
 
+PROJECT_ROOT = _resolve_project_root()
+
+
 class Settings(BaseSettings):
     runtime: RuntimeSettings = RuntimeSettings()
     cors: CorsSettings = CorsSettings()
diff --git a/backend/src/core/logging/config.py b/backend/src/core/logging/config.py
index 6d92ba3..e2cc430 100644
--- a/backend/src/core/logging/config.py
+++ b/backend/src/core/logging/config.py
@@ -6,7 +6,7 @@ from pathlib import Path
 
 import structlog
 
-from core.config.settings import RuntimeSettings, Settings
+from core.config.settings import PROJECT_ROOT, RuntimeSettings, Settings
 from core.logging.formatters import (
     build_plain_formatter,
     build_processor_formatter,
@@ -17,13 +17,20 @@ from core.logging.handlers import build_file_handler_config
 
 
 def _ensure_log_dirs(runtime: RuntimeSettings) -> None:
-    Path(runtime.log_dir).mkdir(parents=True, exist_ok=True)
-    Path(runtime.log_error_dir).mkdir(parents=True, exist_ok=True)
+    _resolve_log_path(runtime.log_dir).mkdir(parents=True, exist_ok=True)
+    _resolve_log_path(runtime.log_error_dir).mkdir(parents=True, exist_ok=True)
+
+
+def _resolve_log_path(path: str) -> Path:
+    candidate = Path(path)
+    if candidate.is_absolute():
+        return candidate
+    return PROJECT_ROOT / candidate
 
 
 def build_logging_config(runtime: RuntimeSettings) -> dict[str, object]:
-    log_dir = Path(runtime.log_dir)
-    error_dir = Path(runtime.log_error_dir)
+    log_dir = _resolve_log_path(runtime.log_dir)
+    error_dir = _resolve_log_path(runtime.log_error_dir)
     formatter_name = "json" if runtime.log_json else "plain"
 
     file_handler = build_file_handler_config(
diff --git a/backend/src/core/taskiq/app.py b/backend/src/core/taskiq/app.py
index 0570f34..12ae6c6 100644
--- a/backend/src/core/taskiq/app.py
+++ b/backend/src/core/taskiq/app.py
@@ -3,10 +3,14 @@ from __future__ import annotations
 from taskiq_redis import ListQueueBroker, RedisAsyncResultBackend
 
 from core.config.settings import config
-from core.logging import configure_logging
+from core.logging import configure_logging, log_service_banner
 
 
 configure_logging(config)
+log_service_banner(
+    service_name=config.runtime.service_name,
+    environment=config.runtime.environment,
+)
 
 def _build_broker(queue_name: str) -> ListQueueBroker:
     return ListQueueBroker(
diff --git a/backend/tests/unit/core/taskiq/test_app.py b/backend/tests/unit/core/taskiq/test_app.py
index ffe32d8..34387d5 100644
--- a/backend/tests/unit/core/taskiq/test_app.py
+++ b/backend/tests/unit/core/taskiq/test_app.py
@@ -22,12 +22,18 @@ def test_taskiq_app_configures_logging_on_import(
     sys.modules.pop("core.taskiq", None)
 
     called = {"count": 0, "args": None}
+    banner_called = {"count": 0, "kwargs": None}
 
     def _fake_configure_logging(*args: object, **__: object) -> None:
         called["count"] += 1
         called["args"] = args
 
+    def _fake_log_service_banner(**kwargs: object) -> None:
+        banner_called["count"] += 1
+        banner_called["kwargs"] = kwargs
+
     monkeypatch.setattr("core.logging.configure_logging", _fake_configure_logging)
+    monkeypatch.setattr("core.logging.log_service_banner", _fake_log_service_banner)
 
     importlib.import_module("core.taskiq.app")
 
@@ -35,3 +41,8 @@ def test_taskiq_app_configures_logging_on_import(
 
     assert called["count"] == 1
     assert called["args"] == (config,)
+    assert banner_called["count"] == 1
+    assert banner_called["kwargs"] == {
+        "service_name": config.runtime.service_name,
+        "environment": config.runtime.environment,
+    }
diff --git a/backend/tests/unit/infra/test_worker_runtime_script.py b/backend/tests/unit/infra/test_worker_runtime_script.py
index 4ca858d..c50ad6b 100644
--- a/backend/tests/unit/infra/test_worker_runtime_script.py
+++ b/backend/tests/unit/infra/test_worker_runtime_script.py
@@ -17,4 +17,17 @@ def test_worker_commands_use_taskiq() -> None:
     assert "core.taskiq.app:bulk_broker" in content
     assert 'pgrep -f "taskiq.*worker"' in content
     assert 'pkill -f "taskiq.*worker"' in content
+    assert 'pgrep -f "gunicorn.*app:app"' in content
+    assert 'pkill -f "gunicorn.*app:app"' in content
     assert removed_runner not in content
+
+
+def test_web_command_uses_uvicorn_only() -> None:
+    content = APP_SCRIPT.read_text(encoding="utf-8")
+
+    assert "uv run uvicorn app:app" in content
+    assert 'WEB_PORT="${SOCIAL_WEB__PORT:-5775}"' in content
+    assert "SOCIAL_WEB__WORKERS" in content
+    assert 'UVICORN_LOG_LEVEL="${UVICORN_LOG_LEVEL,,}"' in content
+    assert "SOCIAL_WEB__GUNICORN__" not in content
+    assert "uv run gunicorn" not in content
diff --git a/backend/tests/unit/test_logging_config.py b/backend/tests/unit/test_logging_config.py
index e6b15d2..4937ed8 100644
--- a/backend/tests/unit/test_logging_config.py
+++ b/backend/tests/unit/test_logging_config.py
@@ -71,6 +71,22 @@ def test_build_logging_config_plain_formatter_when_disabled(tmp_path: Path) -> N
     assert handlers["error"]["formatter"] == "plain"
 
 
+def test_build_logging_config_resolves_default_logs_from_project_root(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    from core.config.settings import PROJECT_ROOT
+
+    monkeypatch.chdir(PROJECT_ROOT / "backend")
+    runtime = Settings().runtime
+    config = build_logging_config(runtime)
+    handlers = _get_handlers(config)
+
+    assert handlers["file"]["filename"] == str(PROJECT_ROOT / "logs" / "app.log")
+    assert handlers["error"]["filename"] == str(
+        PROJECT_ROOT / "logs" / "errors" / "app.error.log"
+    )
+
+
 def _read_last_log_entry(log_path: Path) -> dict[str, object]:
     assert log_path.exists(), f"Expected log file at {log_path}"
     entries = [
diff --git a/backend/tests/unit/test_logging_settings.py b/backend/tests/unit/test_logging_settings.py
index df1c54e..7da0573 100644
--- a/backend/tests/unit/test_logging_settings.py
+++ b/backend/tests/unit/test_logging_settings.py
@@ -2,7 +2,7 @@ from __future__ import annotations
 
 from pytest import MonkeyPatch
 
-from core.config.settings import Settings
+from core.config.settings import PROJECT_ROOT, Settings
 
 
 def test_runtime_settings_defaults() -> None:
@@ -52,3 +52,9 @@ def test_runtime_settings_default_file_names_follow_service_name(
     assert settings.runtime.log_error_dir == "logs/errors"
     assert settings.runtime.log_file_name == "worker-default.log"
     assert settings.runtime.log_error_file_name == "worker-default.error.log"
+
+
+def test_project_root_points_to_repo_root() -> None:
+    assert (PROJECT_ROOT / "backend").is_dir()
+    assert (PROJECT_ROOT / "infra").is_dir()
+    assert (PROJECT_ROOT / "pyproject.toml").is_file()
diff --git a/docs/runtime/runtime-runbook.md b/docs/runtime/runtime-runbook.md
index 7e0f38b..9f4e222 100644
--- a/docs/runtime/runtime-runbook.md
+++ b/docs/runtime/runtime-runbook.md
@@ -272,3 +272,4 @@ docker compose --env-file .env -f infra/docker/docker-compose.yml up -d --force-
 | 2026-03-02 | 文档整理：修正 auth 端点名称（/verifications）、补充 profile 路由文档、修复 L2/L3 验证命令 |
 | 2026-03-02 | 修正 bootstrap 命令：init-job 需要使用 `uv run python -m core.runtime.cli bootstrap` |
 | 2026-03-05 | 新增 Agent Runtime run/resume/events 运维排障流程（Taskiq + Redis + Last-Event-ID） |
+| 2026-03-06 | Web 启动从 gunicorn 迁移为纯 uvicorn，移除 `SOCIAL_WEB__GUNICORN__*` 配置，统一使用 `SOCIAL_WEB__WORKERS` |
diff --git a/infra/scripts/app.sh b/infra/scripts/app.sh
index 20f7524..871458f 100755
--- a/infra/scripts/app.sh
+++ b/infra/scripts/app.sh
@@ -41,20 +41,29 @@ start() {
   . "$ENV_FILE"
   set +a
 
+  UVICORN_LOG_LEVEL="${SOCIAL_RUNTIME__LOG_LEVEL:-info}"
+  UVICORN_LOG_LEVEL="${UVICORN_LOG_LEVEL,,}"
+  WEB_PORT="${SOCIAL_WEB__PORT:-5775}"
+
   if tmux has-session -t "$SESSION_NAME" 2>/dev/null; then
     echo "Error: tmux session '$SESSION_NAME' already exists." >&2
     echo "Hint: tmux kill-session -t $SESSION_NAME" >&2
     exit 1
   fi
 
+  if command -v ss >/dev/null 2>&1; then
+    if ss -ltn | awk '{print $4}' | grep -qE "[:.]${WEB_PORT}$"; then
+      echo "Error: web port ${WEB_PORT} is already in use." >&2
+      echo "Hint: run '$0 stop' or change SOCIAL_WEB__PORT in .env" >&2
+      exit 1
+    fi
+  fi
+
   echo "Starting web + worker processes in tmux session '$SESSION_NAME'..."
 
-  WEB_CMD="cd '$ROOT_DIR' && PYTHONPATH=backend/src SOCIAL_RUNTIME__SERVICE_NAME=web uv run gunicorn app:app --bind \
-${SOCIAL_WEB__HOST:-0.0.0.0}:${SOCIAL_WEB__PORT:-8000} --workers \
-${SOCIAL_WEB__GUNICORN__WORKERS:-2} --worker-class \
-${SOCIAL_WEB__GUNICORN__WORKER_CLASS:-uvicorn.workers.UvicornWorker} --timeout \
-${SOCIAL_WEB__GUNICORN__TIMEOUT:-60} \
---log-level ${SOCIAL_RUNTIME__LOG_LEVEL:-info}"
+  WEB_CMD="cd '$ROOT_DIR' && PYTHONPATH=backend/src SOCIAL_RUNTIME__SERVICE_NAME=web uv run uvicorn app:app --host \
+${SOCIAL_WEB__HOST:-0.0.0.0} --port ${WEB_PORT} --workers \
+${SOCIAL_WEB__WORKERS:-2} --log-level ${UVICORN_LOG_LEVEL}"
 
   WORKER_CRITICAL_CMD="cd '$ROOT_DIR' && PYTHONPATH=backend/src SOCIAL_RUNTIME__SERVICE_NAME=worker-critical uv run taskiq worker core.taskiq.app:critical_broker core.agent.infrastructure.queue.tasks --workers ${SOCIAL_WORKER__GROUPS__CRITICAL__CONCURRENCY:-2}"
   WORKER_DEFAULT_CMD="cd '$ROOT_DIR' && PYTHONPATH=backend/src SOCIAL_RUNTIME__SERVICE_NAME=worker-default uv run taskiq worker core.taskiq.app:default_broker core.agent.infrastructure.queue.tasks --workers ${SOCIAL_WORKER__GROUPS__DEFAULT__CONCURRENCY:-2}"
@@ -88,6 +97,10 @@ stop() {
   fi
 
   echo "Checking for orphaned processes..."
+  if pgrep -f "uvicorn.*app:app" > /dev/null 2>&1; then
+    echo "Killing orphaned uvicorn processes..."
+    pkill -f "uvicorn.*app:app"
+  fi
   if pgrep -f "gunicorn.*app:app" > /dev/null 2>&1; then
     echo "Killing orphaned gunicorn processes..."
     pkill -f "gunicorn.*app:app"
diff --git a/pyproject.toml b/pyproject.toml
index b2c54f6..a864f69 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -25,7 +25,6 @@ dependencies = [
     "taskiq-redis>=1.0.0",
     "supabase>=2.27.2",
     "uvicorn[standard]>=0.40.0",
-    "gunicorn>=25.1.0",
 ]
 
 [project.optional-dependencies]