BACKGROUND: The cognitive process of critical thinking (CT) involves the examination of the existing reasons and an analysis of the information to draw conclusions and make decisions. The goal of the study was to determine how concept mapping (CM) technique affects family medicine residents' capacity for critical thought. MATERIALS AND METHODS: We conducted a randomized controlled trial among family medicine residents aged between 26 and 28 years. A total of 100 residents were involved; over the course of 3 months, 50 residents were exposed to the conventional teaching model and 50 residents to the CM model. Data was collected using California CT skills test (CCTST) modified Arabic version and a self-administered questionnaire. The primary intervention was teaching method, experimental group received CM lessons while control group had conventional lessons. First session was carried out at baseline and second session one week after baseline, whereas 3rd, 4th, and 5th sessions conducted at end of 1st, 2nd, 3rd months, respectively. Both groups were assessed at baseline and at end of 3rd month. Both groups were reassessed at end of three months. Quantitative data was presented as mean and SD, whereas frequencies and percentages used for qualitative data. Pre- and post-intervention CT scores for study groups were compared using t-test or Mann-Whitney U test, as appropriate. Groups were compared on pre- and post-intervention CT grades using Chi-square test. RESULTS: Vast majority (98%) of participants were females, nearly half were 27 year old, and belonged primarily to urban areas (76%). There was no difference in the CT scores between the groups at baseline. The post-intervention CT scores for study group were statistically significantly higher (18.36±2.68) compared to control group (15.94±1.94) (P = 0.001). CONCLUSION: The CM approach was superior to the conventional teaching approach in terms of improving CT.