Objective: To analyze university students' knowledge, attitudes, and beliefs about emergency contraception. Methods: Correlational, cross-sectional research. 556 students were invited through non-probabilistic sampling. A 19-question instrument was used, divided into three sections: beliefs, attitudes and knowledge. The content of the instrument was validated through the participation of experts and has a reliability of 0.79. A descriptive and bivariate analysis was performed. Results: 508 students participated, the average age of 20 ± 3.9 years. Regarding beliefs: 240 women and 157 men understand that conception is the point where sperm and egg come together within the female reproductive system, this response is related to the sex of the students (p = 0.03); attitudes: 41.7% of participants maintain that emergency contraception would only work before sperm and egg join within the female reproductive system, 25% said it would work before implantation occurs; knowledge: 33.7% said they would use emergency contraception within 72 hours, 25.6% would use it within 24 hours. The understanding of how contraception works was related to having sex (p = 0.043). Conclusion: Most of the students interviewed have no knowledge about the mechanism of action, which is to prevent the implantation of the fertilized egg.