The purpose of this study was to investigate how tutor behaviours influence learning in problem-based learning (PBL). A previous study had indicated a significant influence of the tutor's social congruent behaviour on the PBL process and this study further investigates this finding by examining two groups of tutors displaying differences in social congruence. The participants were 77 students under the tutelage of four tutors and a self-report questionnaire ranked two tutors to be more socially congruent as compared to the other two. Student learning was measured by a concept recall test and the results from the analysis of covariance indicated a significant impact of the tutor's social congruent behaviour on learning after the problem analysis phase but not on the self-directed learning and reporting phases. It was concluded that the academic abilities of students and the small number of tutors involved may have affected the results, which led to the second part of this study. A group of 11 tutors were selected and the impact of their behaviours on student achievement measured by the module grade was examined. Results indicated that the tutor behaviours had a greater influence on average students as compared to the academically stronger and weaker students. This finding suggests that students who are academically stronger are not as reliant on the tutor while average students may depend more on the tutor to guide and motivate them in order to achieve the learning goals.