This article focuses on the social responsibility of media microblog，taking media website microblog and newspaper microblog as specific observation objects，selecting 20 high-impact media microblog accounts，and making practical considerations on their social responsibility performance. In 2018，the performance of social responsibility in media microblog was generally good，and the performance of four dimensions of responsibility from good to bad was：information production，social supervision，coordination and cultural education. Among the two kinds of media microblogs，the overall level of responsibility of media website microblogs is higher than that of newspaper microblogs. The results of diachronic analysis show that from 2015 to 2018，the level of social responsibility performance of media microblog has increased year by year. Media microblog should further optimize the content structure and make differentiated positioning，and at the same time use the homepage warning and reward and punishment mechanism to constantly improve the employees’ sense of responsibility.