Science communication activities on social media have become more extensive. This paper takes Sina Weibo accounts @Voice of CAS，@Guokr，and @Nature History Magazineas the objects. This study made quantitative statistics on all content published by three Weibo accounts in 2018，and compared the topics，characteristics of the content，interaction，and the performance in social responsibility of three accounts. The study found that the content of @Voice of CASwas of higher scientificalness，lack of fun，and using scientific context mostly. Its communication model is more inclined to one-way model. The @Nature History Magazineand @Guokrtended to use daily context in science communication. Their communication models were closer to the model of public engagement with science. At the same time，this study also adjusted the evaluation system of social responsibility of new media in a context of science communication，and analyzed the performance of the objects in social responsibility.