This paper studies China’s short-video in the mobile internet era in 2020 from four parts，including overview，focus，problems and trends. Overall，in 2020，with the increasing integration of short-video，live video streaming and e-commerce，the growth rate of users was tending to become slower，and the stickiness was getting stronger. The commercial scale expanded significantly. The duopoly competition of DOU and KUAI was in dynamic equilibrium. Content growth was slowing down. Focusing on the industry，there were two distinct features. Firstly，Short-video Apps strengthened e-commerce live streaming business，and the construction of short-video e-commerce platform began to take shape. Secondly，the duration of short-video became longer，and short-video broke through the boundaries of traditional short-video content，expanded to multi-dimensional content forms. However，in the rapid development of live streaming in e-commerce of short-video Apps，“rollover” accidents occurred frequently，the industry chaos and bubbles emerged. Furthermore，the commercial drive of live selling in the short-video Apps made the creation and production of short-video content affected to a certain extent. Looking forward to 2021，the leading short-video APPS will accelerate the expansion of their boundaries，and content production will present the trend of high quality and professionalization.