Objective To explore the facilitators and barriers of physical activity participation among ovarian cancer patients, and to provide evidence for developing targeted interventions to promote patients′ rehabilitation. Methods A descriptive qualitative study was conducted.Thirteen ovarian cancer inpatients were recruited through purposive sampling to conduct semi-structured in depth interviews.The Capability, Opportunity and Motivation-Behavior (COM-B) Model served as the theoretical framework, and directed content analysis was performed to code qualitative data and extract core themes. Results Three facilitators and three barriers of physical activity participation among ovarian cancer patients were identified.Facilitators included capability factors (a lay belief that "activity is beneficial" driven by health beliefs, and self adjustment during intermittent symptom free periods), opportunity factors (family support and companionship, professional medical guidance, and access to convenient environments and exercise resources) and motivation factors (immediate physical and psychological positive feedback derived from activity, a sense of control over life, and the aspiration to resume normal daily routines).Barriers included capability factors (treatment related symptoms, lack of knowledge regarding exercise prescription, and uncertainty in self-regulation), opportunity factors (over protection by fa-mily members, insufficient professional guidance from the healthcare system, and environmental constraints coupled with limited information access) and motivation factors (low priority given to physical activity and a conservative mindset prioritizing physical safety). Conclusion Physical activity participation among ovarian cancer patients is influenced by capability, opportunity and motivation.Multidimensional interventions should be implemented in the future to improve patients′ exercise capacity, optimize suppor-tive environments from families and medical systems, and strengthen their intrinsic motivation for physical activity, in order to facilitate the adoption of safe, evidence based physical activity behaviors.