ABSTRACT The success of sport events is closely related to volunteer dedication. Sport event organisations must recognise volunteers’ needs and motivate and retain loyal volunteers. However, the approach to motivate sport event volunteers and the role of consistent values, beliefs, and affiliation needs in guiding volunteers’ performance in event duties remain unexplored. This study explored the role of organisational environmental factors in influencing volunteers’ engagement, sense of pride, and intent to continue volunteering. A theoretical model was constructed to verify their inner relations by incorporating person – environment fit, social exchange, and social identity theories. Data were collected from 452 volunteers who participated in two marathon races in China and analysed using structural equation modelling with SmartPLS 4.0. The findings show that perceived organisational support has a positive impact on individual – organisation value congruence and volunteer engagement, thus jointly boosting volunteers’ sense of pride and intent. These findings expand theoretical understanding on the psychological mechanisms of volunteer sport events and optimising volunteer management.