Objective: To determine the perception of the use of chlorine dioxide (CDS) and the degree of knowledge about COVID-19 in medical students of a Peruvian university. Material and methods: Cross-sectional observational study. A virtual survey of 158 medical students from the Jorge Basadre Grohmann National University was conducted from 15 to 18 August 2020. The instrument used was divided into three sections: socio-demographic characteristics, level of knowledge about COVID-19 and attitudes towards the use of CDS. Bivariate analysis was performed using Fisher's exact test. Results: Of the 158 medical students surveyed, 53 % were women, the average age was 21 (RIQ: 19-23) year-old. 22 % consider that if a doctor or health care staff recommends the use of chlorine dioxide, it is because it has some utility in treating COVID-19, and 39 % have low knowledge&n...