There has been limited study regarding patient-provider communication about medical cannabis for cancer symptom management. To address this gap, this study assesses the determinants and prevalence of patient-provider communication about the use of medical cannabis for cancer symptoms at a National Cancer Institute-designated Comprehensive Cancer Center. Individuals who completed cancer treatment from July 2017 to December 2019 were invited to participate in a survey regarding medical cannabis. An electronic survey was administered in English and Spanish from August to November 2021 and completed by 1592 individuals (response rate = 17.6%). About one-third (33.5%) of participants reported discussing medical cannabis for cancer symptom management with a health-care provider. Controlling for other factors, individuals with malnutrition and/or cachexia had higher odds (odds ratio [OR] = 2.30, 95% confidence interval [CI] = 1.50 to 3.53) of reporting patient-provider discussions compared with individuals without malnutrition and/or cachexia. Similarly, individuals with nausea had higher odds (OR = 1.94, 95% CI = 1.44 to 2.61) of reporting patient-provider discussions compared with individuals without nausea. A smaller percentage (15.6%) of participants reported receiving a recommendation for medical cannabis for cancer symptom management. Among individuals who reported using cannabis, a little over one-third (36.1%) reported not receiving instructions from anyone on how to use cannabis or determine how much to take. Overall, our study suggests that patient-provider communication about medical cannabis for cancer symptom management is limited. As interest and use of medical cannabis continues to grow among cancer patients, there is a need to ensure patients have access to high quality patient-provider communication.