Introduction: Patient safety aims to achieve healthcare free of damage. The World Health Organization indicates that this objective is achieved through communication, analysis, and prevention of adverse events in patients. Organizational culture has been identified as one of the main factors for interventions aimed to reduce medical errors; and an essential component of safety culture is the attitude of health professionals towards medical error. Attitudes can be improved through appropriate education in biomedical careers but its inclusion in Argentina is scarce. The Attitudes Questionnaire for Patient Safety, measures knowledge, beliefs, and attitudes about patient safety and could be a useful tool in our country., Objectives: To validate the modified attitudes for patient safety questionnaire to measure knowledges, beliefs, and attitudes of medical students at CEMIC University Institute. To describe the level of knowledges, beliefs, and attitudes in patient safety of medical students at CEMIC University Institute in 2012, 2015 and 2016., Methods: Design: descriptive study. Scope: Exploratory. Setting: the CEMIC University Institute in Buenos Aires, Argentina. Population: medical students of 4th and 5th year. Sampling: a sample size of 100 participants was estimated to derive meaningful estimates as per a Cronbach's alpha> 0.60., Results: The reliability of the instrument (internal consistency) by Cronbach's alpha showed an overall correlation of 0.695. Suitable Cronbach's alpha values were obtained in all categories, except in two: importance of patient safety in the curriculum and the inevitability of error. The responses on knowledge, attitudes and perceptions about patient safety in the three cohorts showed that 57% of students believe they understand concepts about patient safety, 53% consider their training prepares them to understand the cause of medical errors, only 59% believe that human error is inevitable and 98% believe that real professionals do not make mistakes. Lastly, 64% believe that this knowledge is only acquired from clinical experience., Conclusion: This study shows that the APSQ-III modified survey is valid and could be used in Argentina and the region to measure the impact of incorporating patient safety topics in the medical curriculum.