Aim: We performed a systematic review of the evidence for effectiveness and acceptability of different ketogenic diets (KDs) in the therapeutic management of gliomas. Methods: The search strategy included searches of seven electronic databases. Data extraction and quality assessment were undertaken independently by two authors. Results: No randomized clinical trials were identified. Six studies (n = 39) met the eligibility criteria for this review - all were case series or reports and therefore at high risk of bias. All studies reported overall or progression-free survival; however the effectiveness of KD interventions could not be established. Dietary acceptability was not reported. Conclusion: The effectiveness and acceptability of KDs in the management of gliomas is unknown and high quality randomized controlled trials are needed.