It is the first defensive line that regulatory enforcement by the stock exchange plays the monitoring role in supervising listed companies. This study, thus, investigates the association between stock exchange self-regulatory enforcement and firms’ financial reporting quality. The study is conducted by using the sanction and penalty pronouncements regarding supervision of listed companies in the Shenzhen Stock Exchange of China. The results find that the likelihood of sanctions by the stock exchange would increase for firms with the lower reporting quality in the previous year. In addition, the sanctioned firms will improve the accruals quality of its financial reports in the next year.