In light of the importance of sustainable development, this study aims to deepen and extend our understanding of employees’ pro-environmental behaviour in the workplace in a Chinese context. Drawing on the complex phenomenon of social norms theory concerning misperceptions (i.e., pluralistic ignorance) and supervisor–subordinate guanxi (which is a Chinese term signifying human connection), we present a novel model in which employees’ pro-environmental behaviour is the result of multiple social and individual psychological factors. Through the integration of previous literature from the fields of the psychology of individuals, social psychology, and environmental psychology, the major assumption is that the pro-environmental behaviour of employees is affected by their level of pluralistic ignorance, environmental concern, and subjective norms; these, in turn, are influenced by supervisor–subordinate guanxi and social identity in the collective spirit of Chinese society. Data, which were analysed empirically, were gathered from 548 Chinese employees from the Jiangsu province of China. This study consequently reveals the subtle interplay among employees’ pluralistic ignorance, supervisor–subordinate guanxi, social identity, subjective norms, environmental concern, and their pro-environmental behaviour, while the deeper analysis offers considerable support for environmental management research and practice.