Objective: Training of doctors about psychiatric illnesses is crucial for betterment of mental health of the community. In our study we have tried to assess the role of compulsory internship posting of medical undergraduates in Psychiatry department in changing their attitude about mental illnesses towards a more positive side. Method: Sixty–two (62) MBBS interns were included in our study and were assessed by a pre–post study using the Attitude to Mental Illness Questionnaire (AMIQ) before and after their psychiatry posting. Results: There was an initial negative attitude towards injection heroin user, and poor attitude towards schizophrenia prior to internship posting. However, following psychiatry posting, their attitudes changed towards more positive side, and these changes were statistically significant in cases of injection heroin user, depression & suicide, as well as schizophrenia. Conclusion: Compulsory internship posting in psychiatry department plays a very crucial role in changing attitude towards mental illnesses among doctors.