Based on the institutional theory, this article attempts to examine two consecutive questions regarding the impact of various factors on corporate decision in environmental information disclosure (EID): (1) whether or not to disclose; and (2) the level of disclosure. The relevance of these factors is empirically tested using data collected from publicly listed manufacturing companies from 2006 to 2008 in China. Some interesting findings appear. We find that firms that are state-owned, those that operate in environmentally sensitive industries, those having more industrial peers engaged in EID, and those with better reputation are more likely to disclose environmental information. When it comes to the content of EID, variables that attempt to capture external institutional pressures exhibit either no or weak explanatory power. Only the variable of organizational image and reputation is demonstrated to have a significant impact on both the act and the content of EID. This study provides a snapshot of the dialogues between constituencies in the organizational field and EID development.