Background: The existence of stigmatizing attitudes with individuals suffering from mental disorders is unequivocal, timeless and observed even among mental health professionals. The impact of such stigmatization varies from social exclusion to lack of medical support, ending up, at times, in preventable deaths. Medical education institutions still find it difficult to deconstruct the stigma among students, and the search for effective methods, in short and long term, guides the main studies in the area and is also the main focus.Objective: Assess the effects of duration of mental health training in students during the medical internship in reducing the stigmatization of people with mental disorders.Method: A quasi-experimental study to assess the impact of an educational program during the medical internship in mental health. The sample consisted of 70 and 67 medical students in their last year in college, in 2018and 2019, respectively. Questionnaires were applied to assess the extent and typification of stigma, concerning schizophrenia and self-perception on medication management and treatment of psychiatric disorders. The instruments used the Three-Point Likert Scale to assess the results. The questionnaires were applied immediately before and after exposure to the educational program, which lasted four and nine weeks in 2018 and 2019, respectively. The mean values of self-perception and stigma were compared between both occasions using the Student T-test. Results: the mean post-test scores regarding self-perception and stigma did not show significant difference between the classes. Conclusion: Future studies need to observe other potential variables to improve the effectiveness of intervention programs to reduce stigmatization to people in psychic suffering.