Background: Antidepressants are commonly used for the pharmacological treatment of depression. We aimed to summarise the prevalence of antidepressant prescription to cancer patients, and differences by study or patient characteristics. Methods: PubMed, Embase, Web of Science, Scopus and psychINFO were searched using keywords ‘psychotropic’, ‘antidepressants’, ‘prescription’ and ‘cancer’. Prevalence of antidepressants, type, dose and follow-up of antidepressants and prescriber details were extracted. Results: Overall, 1537 articles between 1979 and February 2015 were found, 38 met the inclusion criteria and were reviewed according to PRISMA guidelines. The prevalence rate of prescribing antidepressants to cancer patients was 15.6% (95% CI = 13.3–18.3). Prescription was significantly less common in studies from Asia (7.4%; 95% CI = 4.3–12.5), more common in female (22.6%; 95% CI = 16.0–31.0) or breast cancer patients (22.6%; 95% CI = 16.0–30.9). Selective serotonin reuptake inhibitors were the most frequently prescribed antidepressants. General practitioners and psychiatrists, followed by oncologists, were identified as the major providers of antidepressant prescriptions to cancer patients. Few studies reported the exact dose, length of time drugs were prescribed for or follow-up regimens. Conclusions: There is considerable variation in the prescribing patterns of antidepressants across the world, with few studies reporting robust data on exact dose or follow-up regimens. Prospective studies that monitor antidepressant prescribing, including details of reasons for prescribing and the healthcare providers involved, dose, change in dose or type of medication and follow-up are needed to ascertain whether patients are being treated optimally and if side effects or drug–drug interactions are identified and managed.