Mass gatherings(MGs) are crowded events that attract enough people to exceed the capacity of routine health and public safety measures. WHO defines MGs as ‘events attended by a sufficient number of people to strain the planning and response resources of a community, state or nation. MGs pose serious health risks for attendees, organisers and citizens of the venue city. For effective public health management for all the stakeholders engaged in MGs, the role of psycho-social factors in managing the health-related behaviour of attendees needs to be investigated. Previous research suggests that health risk perception plays a crucial role in shaping individuals’ responses to hygiene, sanitation and crowd dynamics. These responses shape health-related behaviour in special reference to infectious diseases. This paper explored the general health-related behaviour among the attendees of one of India's largest religious mass gatherings held post-COVID outbreak- The Kumbh Mela 2021. It examined the role of shared identity among attendees and its impact on health-related behaviour through perceived risk perception within the special context of Kumbh Mela. A multivariate analysis of a survey study of attendees of Kumbh Mela (N=400) showed that shared social identification leads to better-perceived health and well-being through undermining health risk perceptions in mass gatherings. These findings have important implications for understanding how crowd dynamics may aggravate health risk behaviours in mass gatherings. The present research should contribute to efforts to understand the nature and scope of social identity processes in aggravating and mitigating health behaviour in mass gatherings.