Background Globally, marijuana is becoming an acceptable complementary medicine for symptom management in cancer. At the time that the study was conducted, Zimbabwean laws only allowed for the cultivation of marijuana for medical and scientific use. As of 18 July 2022, the national medicines regulator released a circular allowing the licensing, distribution, and use of cannabidiol-based products. Anecdotes indicate there is medical marijuana use among Zimbabwean patients with cancer. We sought to determine the prevalence, patterns of use and perceptions of medical marijuana among patients with cancer. Methods A cross-sectional survey was used to determine patterns and perceptions of marijuana use among outpatient patients with cancer. The study included adults attending the outpatient oncology clinic at Parirenyatwa Hospital Radiotherapy Treatment Center. Results Fifty participants with a median age of 50.5 years (IQR: 41–58) completed the questionnaire, and 28.0% of them were male. The prevalence of marijuana use in the sample was 24.0% (95% CI 13.9–38.2). Most marijuana users were male (83.3%, p < 0.001). The rate of medical marijuana use among users was 66.7%. Participants were generally neutral concerning the benefits of marijuana and how it should be regulated. Just under 50% indicated that they would be open to using it if it were legal. Conclusions and recommendations The prevalence of marijuana use in the sample was comparable to other jurisdictions. Perceptions toward medical marijuana were generally neutral. Consequently, for medical marijuana and/or cannabidiol-based products to become acceptable in the Zimbabwean context, there is need for the dissemination of evidence-based information on their benefits.