Aim: The study was conducted to determine the knowledge, attitudes and behaviors of university students on rational drug use. In recent years, non-rational drug use has become a global problem.Material and Methods: The developed questionnaire was applied to 640 medical school students, who agreed to participate in the study, with face-to-face interview technique. The questionnaire has items to question the knowledge, attitudes, behaviors of individuals regarding the rational drug use.Results: Of the study group, 54.6% (n=350) uses medicines only prescribed by physicians, 87.5% (n=560) uses drugs in accordance with the prescription, and 27.5% (n=176) stated to store medications under appropriate conditions. Of the respondents, 16.0% (n=103) was taking antibiotics on their own on complaints such as influenza and common cold, 15.5% (n=101) was taking vitamin and mineral supplements every day regularly, and 57.5% (n=368) had never used vitamin-mineral supplements regularly.Conclusion: Non-rational drug use leads to decrease in adherence to treatment, drug interactions, resistance to certain drugs, recurrence or prolongation of the diseases, increased frequency of adverse conditions and increased treatment costs for patients. Of the respondents, 27.66% stated that he/she did not waste any medication, but the remaining 72.34% was wasting drugs more or less. The 81.56% rate of "Yes" response to the question "Would you like to receive training on rational drug use?", despite the 19.22% "Yes" to the "Have you received training on rational drug use?" in our study suggests that there is a need for more education on rational drug use.