Transport sustainability has become a major challenge worldwide. On-demand shared ride-hailing (OSR) is an alternative transport mode to private motorized mobility which allows passengers to share a vehicle and driver to their respective destination. OSR is more flexible than buses and cheaper than taxis. Additionally, ride-hailing services such as OSR play an important role in servicing communities with poor access to public transport (e.g., buses or trains) and people with increased vulnerabilities (e.g., women with children or people with disabilities). The present study investigates the impact of psychological factors on passengers' intention to use OSR services. To achieve this, the Theory of Planned Behaviour (TPB) was used and extended with perceived risk, price sensitivity, and perceived green value. Data were collected from 520 ride-hailing passengers in Vietnam. The results confirm the relevance of the original TPB constructs, i.e., attitudes, perceived behavioural control, and social norms. Concerning the three additional constructs, only perceived risk negatively and directly influences usage intention, while the two other constructs (i.e., price sensitivity and perceived green value) influence the intention to use OSR via attitudes. The results also reveal that the impact of perceived green value on usage intention is higher among females than males. Additionally, among middle- and high-income people, there is a significant negative association between perceived risk and intention, while this association is not significant among low-income participants. The findings from the present paper provide evidence of the importance of psychosocial factors such as perceptions of risk, price sensitivity, and sustainability when considering intention to use on-demand shared transport services.@en