BACKGROUND Disciplinary-based information literacy (DIL) or professional-related information literacy has not been widely studied in the academic context, including medical sciences. This study aimed at investigating the status of DIL among medical students in an Iranian medical university. METHODS This study was a cross-sectional survey. A random sample consisting of 298 students majoring in general medicine at Tehran University of Medical Science, Tehran, Iran, in the academic year of 2018-2019 completed a valid and reliable 20-item questionnaire on DIL. Data were analyzed using SPSS statistical software. RESULTS Participants' DIL was less than expected, especially in the skills related to professional information access and evaluation. The majority of them had low DIL level. However, medical students in their last 2 years of study had significantly high scores in DIL than those in their first 2 years of study. CONCLUSIONS Information literacy has not been seriously considered in health-related higher education in Iran. It is needed to consider DIL in the medical curriculum for training students to be proficient specialists in medical practice.