Objective: To identify the perceptions of implementing online cooperative learning during the 2021 II academic semesterby first-year students of Universidad Nacional Mayor de San Marcos (UNMSM) School of Medicine. Materials and methods: A descriptive and cross-sectional research design was used in this study. The population consisted of 592 students from the professional schools of Human Medicine, Nursing, Obstetrics, Nutrition and Medical Technology. A random probability sampling was carried out and a sample of 429 students was obtained. The Cooperative Learning Questionnaire with an 8-point Likert scale response format developed by McLeish was used as an instrument for data collection. It is a reliable and valid instrument that was administered online to the sample of students at the end of the course using Google Forms. The quantitative data were analyzed descriptively using IBM SPSS ...