The design of the client for an embedded video monitoring system based on B/S structure is mainly introduced. It emphasizes on the imple- mentation of the buffer mechanism when receiving H. 264 data with RTP protocol. The method used in the video decoding and displaying process using FFmpeg and SDL are also elaborated. In the end, the application method of ActiveX component in video monitoring is introduced. The experimental re- sult shows that the client can achieve the monitoring on remote place, and it is easy to use.