Background: Knee osteoarthritis is a common musculoskeletal disorder associated with pain, impaired mobility, and reduced quality of life. Therapeutic exercise is an important component of conservative management, although the comparative benefits of different physiotherapy approaches require further evaluation.Objective: To compare the effects of progressive resistance training and conventional physiotherapy on pain intensity, functional mobility, and knee-related disability in individuals with knee osteoarthritis.Methods: A comparative interventional study was conducted among 380 participants with clinically diagnosed knee osteoarthritis at DSP Physiotherapy Clinic, Hisar, Haryana, India, between October 2025 and January 2026. Participants were allocated to progressive resistance training (Group A; n = 190) or conventional physiotherapy (Group B; n = 190). Outcomes were assessed before and after the intervention using the Visual Analogue Scale (VAS), Timed Up and Go (TUG) test, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).Results: Both groups demonstrated improvements in pain, functional mobility, and knee-related disability. Mean VAS scores decreased from 6.70 to 4.49 in Group A and from 6.60 to 5.12 in Group B. TUG completion times improved from 14.80 to 11.78 seconds and from 14.60 to 12.61 seconds, respectively. WOMAC scores decreased from 52.00 to 36.03 in Group A and from 51.50 to 41.02 in Group B.Conclusion: Progressive resistance training showed greater numerical improvements across all three outcomes than conventional physiotherapy. Verification of the statistical analyses using the original dataset is necessary before confirming comparative effectiveness.