As a vital channel for enterprises to convey corporate environmental responsibility, the information validity and textual features of environmental disclosure are increasingly concerned. From a new perspective of textual tone, we explore the impact of environmental information disclosure tone on corporate green innovation based on the sample of Chinese A-share listed manufacturing enterprises from 2010 to 2020 and future analyze the different functions of regulative, normative, and cognitive institutional factors. Applying text mining and Poisson regression models, we find that the net positive tone of environmental information and its degree of dispersion can enhance information transparency, improve stakeholders’ positive expectations, and have positive information and resource effects on corporate green innovation. And the concentrated negative tone could alleviate negative reactions. Furthermore, the results indicate that under external pressures of the regulative institution of government supervision and the normative institution of media attention, the signaling role of information tone is enhanced, while the cognitive institution of executive environmental cognition exerts an inhibitory effect. Additional analyses suggest that the effect of environmental disclosure tone on green innovation is more pronounced in enterprises that are non-state-owned, lightly polluted, and located in economically developed areas. Information readability also plays a reinforcing role. This paper substantiates the signal function of environmental information intonation, which enriches the study of the language features of non-financial information and has implications for the perfection of environmental institutions.