OBJECTIVE: Healthy eating and physical activity may help endometrial cancer survivors (ECS) improve their quality of life. However, most ECS do not meet the relevant guidelines. This pilot trial aimed to test the study feasibility procedures for a definitive trial of a behavioural lifestyle programme. DESIGN AND SETTING: This 24-week parallel two-arm randomised pilot trial took place in two hospitals in London, UK (April 2015-June 2016). PARTICIPANTS: Sixty disease-free ECS within 3 years of diagnosis. INTERVENTIONS: Participants were randomised using minimisation to receive the intervention or care as usual. The 'Shape-Up following cancer treatment' programme used self-monitoring, goal-setting, self-incentives, problem-solving and group social support for 12 hours over 8 weeks to help survivors improve their eating and physical activity. OUTCOME MEASURES: The main outcome measures were recruitment, adherence, and retention rates. Further outcomes included barriers to participation and feedback on programme satisfaction. RESULTS: Of the 296 potentially eligible ECS, 20% (n=60) were randomly allocated to the active intervention (n=29) or control group (n=31). Three participants in each arm were deemed ineligible after randomisation and excluded from analysis. Twenty participants (77%; 95% CI 61% to 93%) adhered to the intervention and provided generally favourable feedback. At 24 weeks, 25/26 (96%; 95% CI 89% to 100%) intervention and 24/28 (86%; 95% CI 73% to 99%) control participants completed their assessment. No intervention-related adverse events were reported. Among eligible survivors who declined study participation (n=83), inconvenience (78%; 95% CI 69% to 87%) was the most common barrier. CONCLUSIONS: The trial was feasible to deliver based on the a priori feasibility criteria. Enhancing recruitment and adherence in a definitive trial will require designs that promote convenience and consider ECS-reported barriers.