Objectives: Patient safety competencies (PSC) of nursing students are, in particular, critical for quality and safe care. In the study, it was aimed to determine the PSC of nursing students and the factors affecting them. Methods: This descriptive cross-sectional, relationship-seeking, and comparative study was conducted between February 1st and May 15th, 2022. The sample of the study consisted of 441 students studying at three universities. The data were collected online using the Sociodemographic Data Form and PSC Self-Evaluation Tool. Results: In institutions where the study was conducted, students rated their level as above moderate in the PSC. Those aged 23 and over, and those who had received education on patient safety in patient care and drug administration were found to have a higher level of PSC. When the scores that all students obtained from the overall scale and its subscales were compared, it was determined that students of University C had statistically higher overall and subscale scores than those in the other two universities. Conclusion: The assessment of PSC and the determination of the influencing variables may shed light on the regulations to be conducted in this regard. Patient safety courses should be included in the nursing curriculum as a compulsory course in two semesters at basic and advanced levels.