The number of Indonesian students in higher education has been increasing rapidly. However, many Indonesian university students report experiencing mental distress. Research on student wellbeing found that self-compassion (i.e., being kind towards oneself in challenging times) and academic engagement (i.e., a commitment and purposeful effort toward study) are essential to students’ mental wellbeing. With the present study, we aimed to assess the mental wellbeing of Indonesian students. A convenience sample of 156 Indonesian students completed self-report measures on mental wellbeing, self-compassion and academic engagement (consisting of vigour, dedication and absorption). To contextualise their mental wellbeing, data from Indonesian students were compared with those from 145 UK students using Welch t-tests. Correlation, regression and mediation analyses were then performed to examine the relationships among these variables. Indonesian students had higher levels of self-compassion and absorption and a lower level of dedication than UK students. Self-compassion and academic engagement explained 36% of variance in mental wellbeing. Self-compassion and vigour were identified as significant predictors of mental wellbeing, whereas self-compassion was the strongest predictor. Lastly, vigour did not mediate the pathway from self-compassion to mental wellbeing. Interventions to support self-compassion and academic engagement, especially vigour, in Indonesian students are recommended to support their mental wellbeing.