OBJECTIVE To measure the acceptance of problem based learning (PBL), to find out if they consider that spending extra-time is worthy, how they perceive their own learning, and how it correlated with other learning parameters. METHODS After exposure to PBL during one semester, a cross sectional survey based on Likert-type scale was conducted to measure the students' opinion about PBL acceptance and perception of their own learning. The sample was 268 (65%) females and 143 (35%) males from the 3rd semester of the medical school. The Spearman's correlation was used for analysis. RESULTS PBL was considered to be useful or very useful for their learning to 89% of the students. The PBL used longer time working after the classroom activities. The extra-time spent in the course was considered worthy by 77%. Perception of their own learning correlated with the marks that they obtained (rho=0.202, p<0.0001), and with the acceptance of PBL (rho=0.291, p<0.0001). CONCLUSIONS Students' acceptance of PBL was corroborated. Perception of a better learning correlated with higher marks and, with better acceptance of PBL and with the perception that the additional time spent was worth while.