Most women with ovarian cancer are diagnosed at an advanced stage (stage III or IV), when the intraabdominal spread of the tumour impacts nutrient intake and absorption. Up to 70 % of women with ovarian cancer are malnourished and approximately 40 % are affected by muscle loss at the time of diagnosis. Women with ovarian cancer are at high risk of nutritional decline due to invasive treatment and the severity of side-effects. This review explores the evidence evaluating nutritional interventions during treatment for ovarian cancer and their effect on nutritional status, muscle mass, and clinical outcomes. Perioperative immunonutrition has been investigated with mixed results for immediate postoperative outcomes. Individualised nutrition counselling as part of a multimodal prehabilitation programme prior to surgery shows promising results; however, the effects are limited by sample size. Nutrition counselling as part of a mixed intervention with exercise shows high acceptability and suggests improvements in dietary intake and quality of life during chemotherapy treatment, while oral nutritional supplements and nutrition education appear to reduce symptom burden. Individualised nutrition counselling during treatment also appears to be associated with improved overall survival; however, the evidence is limited to a single retrospective study. A key finding from this review is that, despite the high prevalence of malnutrition and muscle loss in women with ovarian cancer and the critical importance of addressing these modifiable prognostic factors, nutrition intervention studies are limited. Prospective studies with samples large enough to provide adequate power to evaluate intervention effectiveness are urgently required to inform optimal management.Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.