Abstract: The Advances in wireless communication and mobile computing techniques provide new venues to support novel live streaming systems.However,the dynamics of network as well as the realtime requirement of streaming service impose additional challenges on the implementation.In this paper,we design and implement a mobile live video streaming system over Android based smartphones.The implemented system enables users to capture the onspot video with the video camera embedded in smartphone and upload to the media server via either WiFi or 3G networks,providing live and/or on-demand streaming services to remote users.We describe the design and implementation mechanism of the key components involved in the system,including video capturing/encoding,video processing/publishing and video playback.In addition,we also evaluate and compare the encoding and transmission performance of the system over different scenarios.