Abstract: The voice of minority investors through the exchange’s interaction platform helps to convey investors’ information needs to companies. Therefore, it is meaningful to explore whether investors’ attention can improve information disclosure quality of listed firms. Taking the listed A-share firms from 2010 to 2020 as an example, this paper crawled the text information of investors’ questions from the exchange’s interaction platform using Python and set the variable “investors’ attention”. Then, the research explored the impact of investors’ attention on the quality of information disclosure, as well as the mechanism role of board secretary between investors’ attention and the quality of information disclosure. The results showed that: (1) Investors’ attention improved the quality of information disclosure of listed firms. Further, this improvement could reduce the risk of stock price crash, and improve the protection of minority investors. (2) Duality positions and professional background of board secretary play a moderating role between investors’ attention and the quality of information disclosure, especially the position of vice president and the financial or technical background. (3) Further research found that good information environment and good governance environment can significantly enhance the impact of investors’ attention on the quality of information disclosure. The moderating effect of board secretary’s duality positions is more significant in firms with poor information environment and good governance environment, while the moderating effect of board secretary’s background is just the opposite. The findings of this study suggest that board secretary’s duty facilitates the transfer of information between firms and investors, which helps to improve the protection of minority investors.