diff --git a/handlers/base.py b/handlers/base.py
index ca14fb9..93e9a84 100644
--- a/handlers/base.py
+++ b/handlers/base.py
@@ -42,19 +42,21 @@ if TYPE_CHECKING:
 logger = logging.getLogger(__name__)
 
 
-def get_video_encode_args(hw_accel: str = HW_ACCEL_NONE) -> List[str]:
+def get_video_encode_args(hw_accel: str = HW_ACCEL_NONE, maxrate: Optional[int] = None) -> List[str]:
     """
     根据硬件加速配置获取视频编码参数
 
     Args:
         hw_accel: 硬件加速类型 (none, qsv, cuda)
+        maxrate: 最大码率（bps），用于限制 CRF/CQ 模式的峰值码率。
+                 例如 4000000 表示 4Mbps。bufsize 自动设为 maxrate 的 2 倍。
 
     Returns:
         FFmpeg 视频编码参数列表
     """
     if hw_accel == HW_ACCEL_QSV:
         params = VIDEO_ENCODE_PARAMS_QSV
-        return [
+        args = [
             '-c:v', params['codec'],
             '-preset', params['preset'],
             '-profile:v', params['profile'],
@@ -64,7 +66,7 @@ def get_video_encode_args(hw_accel: str = HW_ACCEL_NONE) -> List[str]:
         ]
     elif hw_accel == HW_ACCEL_CUDA:
         params = VIDEO_ENCODE_PARAMS_CUDA
-        return [
+        args = [
             '-c:v', params['codec'],
             '-preset', params['preset'],
             '-profile:v', params['profile'],
@@ -76,7 +78,7 @@ def get_video_encode_args(hw_accel: str = HW_ACCEL_NONE) -> List[str]:
     else:
         # 软件编码（默认）
         params = VIDEO_ENCODE_PARAMS
-        return [
+        args = [
             '-c:v', params['codec'],
             '-preset', params['preset'],
             '-profile:v', params['profile'],
@@ -85,6 +87,14 @@ def get_video_encode_args(hw_accel: str = HW_ACCEL_NONE) -> List[str]:
             '-pix_fmt', params['pix_fmt'],
         ]
 
+    # CRF/CQ + maxrate 上限：保留质量控制的同时限制峰值码率
+    if maxrate and maxrate > 0:
+        maxrate_k = f'{maxrate // 1000}k'
+        bufsize_k = f'{maxrate * 2 // 1000}k'
+        args.extend(['-maxrate', maxrate_k, '-bufsize', bufsize_k])
+
+    return args
+
 
 def get_hwaccel_decode_args(hw_accel: str = HW_ACCEL_NONE, device_index: Optional[int] = None) -> List[str]:
     """
@@ -579,14 +589,17 @@ class BaseHandler(TaskHandler, ABC):
 
     # ========== FFmpeg 参数生成 ==========
 
-    def get_video_encode_args(self) -> List[str]:
+    def get_video_encode_args(self, maxrate: Optional[int] = None) -> List[str]:
         """
         获取当前配置的视频编码参数
 
+        Args:
+            maxrate: 最大码率（bps），用于限制峰值码率
+
         Returns:
             FFmpeg 视频编码参数列表
         """
-        return get_video_encode_args(self.config.hw_accel)
+        return get_video_encode_args(self.config.hw_accel, maxrate=maxrate)
 
     def get_hwaccel_decode_args(self) -> List[str]:
         """
diff --git a/handlers/compose_transition.py b/handlers/compose_transition.py
index edd0076..debe9ae 100644
--- a/handlers/compose_transition.py
+++ b/handlers/compose_transition.py
@@ -250,7 +250,7 @@ class ComposeTransitionHandler(BaseHandler):
         ]
 
         # 编码参数（根据硬件加速配置动态获取）
-        cmd.extend(self.get_video_encode_args())
+        cmd.extend(self.get_video_encode_args(maxrate=output_spec.bitrate))
 
         # 帧率
         fps = output_spec.fps
diff --git a/handlers/render_video.py b/handlers/render_video.py
index c7e8087..25f176c 100644
--- a/handlers/render_video.py
+++ b/handlers/render_video.py
@@ -11,7 +11,7 @@ import logging
 from typing import List, Optional, Tuple
 from urllib.parse import urlparse, unquote
 
-from handlers.base import BaseHandler, VIDEO_ENCODE_ARGS
+from handlers.base import BaseHandler
 from domain.task import Task, TaskType, RenderSpec, OutputSpec, Effect, IMAGE_EXTENSIONS
 from domain.result import TaskResult, ErrorCode
 
@@ -492,7 +492,7 @@ class RenderSegmentTsHandler(BaseHandler):
             '-vf', vf_filter,
         ]
 
-        cmd.extend(VIDEO_ENCODE_ARGS)
+        cmd.extend(self.get_video_encode_args(maxrate=output_spec.bitrate))
 
         fps = output_spec.fps
         cmd.extend(['-r', str(fps)])
@@ -628,7 +628,7 @@ class RenderSegmentTsHandler(BaseHandler):
             cmd.extend(['-vf', filters])
 
         # 编码参数（根据硬件加速配置动态获取）
-        cmd.extend(self.get_video_encode_args())
+        cmd.extend(self.get_video_encode_args(maxrate=output_spec.bitrate))
 
         # 帧率
         fps = output_spec.fps