ObjectivesSuffering is common among patients with advanced cancer. The practice of mindfulness during patient care can potentially reduce suffering. We aimed to examine the efficacy of mindfulness-based supportive therapy (MBST) on reducing suffering in patients with advanced cancer.MethodsWe conducted a parallel-group, single-blinded, randomised controlled trial at the University of Malaya Medical Centre, Malaysia. Seventy-three patients with advanced cancer with an overall suffering score ≥4/10 based on the Suffering Pictogram were recruited and randomly assigned into either the MBST group (n=34) or the control group (n=39).ResultsThere was a statistically significant reduction in the overall suffering score in the MBST group compared with the control group (U=432.5, median1=−2.0, median2=−1.0, z=−2.645, p=0.008). There was also significant improvement in the total Hospital Anxiety and Depression Scale score (U=483.5, median1=−4.0, median2=−3.0, z=−1.994, p=0.046), and the total Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being score (U=252.0, median1=+14.5, median2=+5.0, z=−4.549, p=0.000) in the MBST group compared with the control group.ConclusionsThe results provided evidence that the practice of MBST during patient care could promote positive psychosocial outcomes.