Students’ psychological resources and positive academic experiences play a significant role in students’ engagement, presenting itself as a fundamental variable in the excellence of academic results (grades, retention, future competent professionals). In this way, the present investigation intends to verify the relation between personal resources (i.e., self-efficacy, optimism, hope, positive emotions) and academic success, being mediated by engagement. It was conducted an observational analytic-transversal study with 307 Portuguese students with a mean age of 24.7 years old, attending university courses. To test the model Structural Equation Modelling analysis was conducted. Results show that engagement fully mediates the relation between personal resources and academic success. The whole model tested reveals that engagement is explained in 52% by personal resources, and academic success is in 26% explained by engagement. Thus, the present investigation intends to contribute to the understanding of students-academic success process analysis, underlying the importance of positive factors in academic settings, specifically of engagement, to achieve good academic results.