BackgroundThe 2022 revised version of the Model Core Curriculum (MCC) for Medical Education in Japan includes “generalism” as a new expertise quality and ability, based on the results of surveys of experts in health professions education. However, the perspectives of medical trainees under the pre‐2022 MCC revision were under‐examined. Here, we investigated what these trainees felt they had learned about general medicine (GM)‐related topics.MethodsWe performed a nationwide cross‐sectional study using an anonymous online questionnaire, which was developed with reference to the 2022 revised MCC. The questionnaire consisted of 14 items. For all items, we asked, “Did you learn enough during medical school?” Respondents were asked to respond on a 5‐point Likert scale (from 1 = strongly disagree to 5 = strongly agree).ResultsThree hundred and eighty‐six participants (response rate 55.4%) were included in the analysis. For the item “Behavioral science,” the number of participants who chose “3 = neither agree nor disagree” was highest, at 171 (44.3%) and with an average of 3.28, indicating that this item was perceived as insufficiently studied. Approximately half of the participants chose “4 = agree” for all items other than “Behavioral science.”ConclusionsThe study suggested that behavioral science may be underlearned among medical trainees of the pre‐2022 MCC generation. Medical educators in Japan should formulate curricula in accordance with the 2022 revision MCC and improve curricula regarding behavioral science. Future research should survey the generation of trainees who receive 2022 revision MCC‐compliant medical education; comparison of results with those of this study would be valuable in examining the effects of the revised guideline and inform international medical educators.