Introduction: This study analyzes the social competence of university students of the Music Education Teaching Degree through variables group climate, team cohesion and social skills. The need to develop good social competence was the basis to implement a project based on the musical theater applied according to the collaborative learning methodology. Method: A group of 58 university students enrolled in year 2 of Music Education started the musical expression practices as part of the research. A longitudinal quasi-experimental design with pretest-posttest phases was used. The musical theater education project with implementation based on collaborative work was selected as an independent variable. To assess social competence, the CCSES (Questionnaire Social Competence in Higher Education) questionnaire was adapted from the Group Climate Questionnaire-Short Form (GCQ-S), the Group Cohesion Evaluation Questionnaire (GCEQ), and the Social Skills Scale. Results: The results show statistically significant differences (p less than 0.05) in the three social competence variables after participating in the collaborative Musical Theater Project-based educational methodology. While climate variables and social skills group differences in the posttest were favorable, group cohesion differences were not. The average in social competence did not differ significantly between the pretest and posttest phases. Discussion and conclusions: The results of this study confirm that the collaborative Musical Theater Project work led to changes in students' social competences. The different proposals to explain the changes noted in all three variables are group climate, team cohesion and social skills. (Contains 5 tables.)