Polycystic ovary syndrome (PCOS) is an endocrine disorder affecting 10-13% of reproductive-aged women. Lifestyle management through diet and physical activity changes can improve reproductive, metabolic, and psychological comorbidities. The aim of this systematic review is to understand the barriers and facilitators to lifestyle changes from the perspective of people with PCOS and health care professionals (HCP) using the theoretical domains framework and capability, opportunity, motivation, and behavior model. Six databases were systematically searched for qualitative, quantitative, and mixed-methods studies to 22nd September 2022. Quantitative outcomes from quantitative and mixed-methods studies were narratively synthesized and all studies were thematically analyzed. Sixty-eight papers met the eligibility criteria. HCP education on lifestyle management in PCOS was viewed by all to be inadequate, impacting the quality of care and health outcomes. Lifestyle advice delivered by a multidisciplinary team, including dietitians, was identified as a key component for change. All agreed that there was a need for individualized and PCOS-specific lifestyle advice. Weight stigma was identified as negatively impacting both those in larger and smaller bodies with PCOS, reducing the quality of care and affecting self-perception and mental health. People with PCOS perceived that lifestyle management was overly focused on weight loss and fertility, independent of their own personal motivations and goals. Systemic changes, including increasing HCP education on lifestyle management and multidisciplinary collaboration, focusing on lifestyle advice that meets individual needs, and reducing the use of weight-centric care are necessary for long-term sustainable changes and improvements in health outcomes in people with PCOS.