Mindfulness-based intervention with adults has been found to be highly effective and as such it has been the subject of much research in the past few decades. However, the study of mindfulness-based approaches with adolescents, especially in the Asian context, is still under-explored. This paper reports findings from a pilot controlled trial assessing preliminary outcomes of a mindfulness-based programme in schools in Hong Kong. Fourteen to 16-year-old adolescents with low academic performance from two secondary schools were invited to take part in intervention and control groups (n = 48). It was hypothesised that a six-week mindfulness-based programme would increase well-being, reduce stress and symptoms of depression. Well-being, stress and depressive symptoms of both intervention and control groups were assessed at baseline and post-intervention. The findings showed that there was a significant decrease in symptoms of depression and a significant increase in one dimension of well-being among both groups. Qualitative data reflected that the mindfulness programme was beneficial and feasible to adolescents at schools. The results support conducting a randomised controlled trial with a larger sample and a long term follow-up.