The regulatory issue of whether listed companies should be required to publish quarterly financial statements has sparked debates in developed capital markets in recent years. This study utilizes the Chinese National Equities Exchange and Quotations’requirement that firms in the Innovative Tier should disclose quarterly reports since 2018 as a natural experiment to conduct regression discontinuity analysis. Our findings indicate that mandatory quarterly reporting enhances investment efficiency among firms in the Innovation Tier by improving information transparency, enabling minority shareholders to better fulfill their monitoring and governance roles. Further analysis reveals that the positive impact of mandatory quarterly reporting on investment efficiency is more pronounced in firms with higher R&D activities, whereas the effects are more modest in firms with higher audit quality, a more developed financial market, and a stronger legal environment. Additionally, mandatory quarterly reporting primarily curbs excessive investments in relatedparty M&A transactions by firms. This paper provides empirical evidence for considering convergence and differences in information disclosure rules between developed and emerging markets.