With the diversification of information transmission forms, internet new media like microblogs constantly becomes an important path of information disclosure in listed companies. By manually collecting the data of companies who disclose information through Sina Weibo, this paper studies performance information disclosure through microblogs, and analyzes the possibility of establishing investment portfolios by irrational behavior of investors based on repetitive performance information disclosure through microblogs to pursue profits. It arrives at the conclusions as follows: after repetitive good information ( like sound performance information) disclosure through microblogs, stock prices rise; and stock prices in companies without good information disclosure through microblogs do not increase. Further study shows that companies who repeat performance information disclosure through microblogs have better future financial performance, that’s why the management of list companies dares to repeat the performance information disclosure through microblogs. It offers empirical evidence for the formulation of corresponding rules and institutions by regulatory authorities and useful reference for investment decision-making of investors.