Many medical practitioners provide care to patients for whom radiotherapy [radiation oncology (RO)] is a recommended treatment or who have received radiotherapy treatment for cancer. A basic level of understanding about this modality is important to ensure a continuum of good patient care. This study aimed to explore the current teaching practices in RO across medical schools in Canada and understand the perception of RO as a career choice among final-year medical students. Ethics approval and/or consent was obtained from each medical school prior to sending an electronic survey to the Undergraduate Medical Education office and to the final-year medical school class. Only six of the 14 Canadian medical schools participated in the surveys. Four of the 14 refused external surveys. The response rate was 8 % (155/1,917) for all final-year medical students and 17 % (155/897) for students from participating medical schools. Didactic lectures are the primary means of delivering RO knowledge. One in five students reports that they did not receive any RO teaching, and 65 % received <2 h. The level of interest in RO as a career choice (scale of 1–5) was greater in students who received >2 h of RO teaching (2.85 vs. 3.18, p = 0.012) and those that took part in a RO elective (2.86 vs. 3.53, p < 0.001). This study confirms the underrepresentation of RO teaching within the Canadian undergraduate medical curriculum. Interest in this specialty is minimal but does appear to be influenced by exposure to RO teaching. It is important to highlight the limitations of conducting a survey study within the Canadian medical undergraduate system. Steps to conduct such studies in a more seamless fashion are required, in order to assist curriculum development in RO and enhance the understanding of the specialty as a career choice.