As one of the innovative regulatory methods, the Annual Report Inquiry Letter has received widespread attention from both the practical and academic sectors for its regulatory effectiveness. The paper takes listed companies in China from 2015 to 2020 as a sample, and uses Python software to process positive and negative word data from the annual report inquiry letter of the Shenzhen Stock Exchange. It tests the impact of flexible regulation of annual reports on the risk of stock price collapse from the degree of negative tone. The study has found that flexible regulation of Annual Reports can play a role, and there is a significant negative correlation between the negative tone of the Annual Report Inquiry Letter and the risk of stock price collapse of listed companies. After further analysis of the negative degree of different intonation in the Annual Report Inquiry Letter, it was found that when the intonation is low, flexible regulation of the Annual Report can reduce the risk of stock price collapse; However, as the negative tone of voice increases, flexible regulation of Annual Reports becomes difficult to play a role. In the future, exchanges should improve the quality of inquiries, regulatory authorities should improve institutional construction, listed companies should strengthen information disclosure, and investors should pay attention to the tone indicators of Annual Report Inquiry Letter to better play the role of flexible supervision in Annual Reports.