Abstract: Reasonable buffer design plays a key role in video stream's decoding and rendering at the receiver side. According to the continuity of packed video data and best-effort character of Internet, a time-driver-based buffer is proposed. And a test method is also introduced to control the packet drop-out and disorder. The performance evaluation of the buffer is done by contrast with no buffer and buffers of different size. The result indicated that this buffer performed well in smoothing video display and could resolve packet drop-out and disorder problem. The proposed design has widely been applied to a certain large-scale client system receiving real-time video stream.