Textual analysis and the Entropy-TOPSIS method are used in this research to create a measure of corporate environmental protection, and multiple regressions are used to find out how digitalization affects corporate environmental protection. The research sets up a theoretical framework for how corporate digitalization affects environmental protection and looks into how external financing constraints and an organization’s own financial position play a role in the middle. The research then looks at how outside factors like the business environment of the market and the level of competition in the industry affect the relationship. Using a threshold regression approach, the research also examines the change in the impact of digitalization on environmental protection after investor sentiment crosses the threshold from the distinct perspective of investor sentiment. Our research provides theoretical support for environmental protection by corporations and government policy direction.