INTRODUCTION: Knee osteoarthritis (OA) is a weight-bearing joint disease and is more common in overweight and obese persons. The objective of this study was to determine the role of rehabilitation exercises (REs) of lower limbs on weight, functional strength, and exercise adherence in overweight and obese knee OA patients. MATERIALS AND METHODS: The patients were recruited from the urban community of Lahore, Pakistan. The patients were divided into the rehabilitation group (RG) and control group (CG). The patients in the RG performed the REs of lower limbs and followed the instructions of daily care (IDC), while the patients in the CG only followed the IDC for a 12 weeks period. Outcome measures were assessed at pre-test before grouping and post-test after 12-weeks of interventions. The measures included: weight, functional strength, and exercise adherence. The Paired Samples t-test (for normally distributed data) and the Wilcoxon Signed Ranked Test (for data that was not normally distributed) were used to analyze the differences within groups from pre to post-test measurements. The variance 2 × 2 factors and the Mann Whitney U-test were used to analyze the difference in weight and functional strength between the groups. RESULTS: The patients in the RG reported a statistically significant weight reduction (p < 0.001) and improvement in the functional strength (p < 0.001) within a group. Similarly, the patients in the CG also reported a significant improvement in the scores of functional strength (p = 0.004) within a group. The improvement in the scores of functional strength was higher in the patients of RG than the CG (p < 0.001). Similarly, the patients in the RG reported a statistically significant reduction in weight than the CG (p < 0.001). CONCLUSION: The REs could improve weight, functional strength and exercise adherence.