Destination crowding has emerged as a serious issue for tourist sites and visitors alike. This research delves into the correlation between two‐dimensional perceived (spatial and human) crowding and two tourist behaviors (pro‐environmental and deviant behavior). Additionally, it explores the influence of deindividuation and environmental knowledge on these relationships. The study, based on 313 Chinese domestic tourists who recently visited the Great Wall, reveals that perceptions of spatial and human crowding significantly trigger deviant behavior. Conversely, pro‐environmental behavior is indirectly impeded by both forms of perceived crowding, with deindividuation acting as a mediating factor. The presence of environmental knowledge proves crucial in empowering tourists to make well‐informed behavioral decisions and mitigating the negative effects of deindividuation on their actions. This research contributes to the tourism literature by incorporating deindividuation to enhance the understanding of how perceived crowding affects tourist behaviors. It further advances the field by differentiating between pro‐environmental and deviant.