Sixty patients with bilateral stage 2 or 3 knee osteoarthritis were randomized to receive either high-intensity laser therapy (HILT) with exercise (n=30) or short-wave diathermy (SWD) with exercise (n=30) over a two-week period. The primary outcome of interest was pain reduction as measured by the Visual Analogue Scale (VAS). Secondary outcomes included physical function (WOMAC, Timed Up and Go, Stair Climb, 30-s Chair-stand, and 40-meter Fast-paced Walk) and quality of life (SF-36). Outcomes were assessed before and after the two-week intervention. Overall, the results of the study revealed that both interventions improved pain and function, but high-intensity laser therapy was superior in most measures including VAS, WOMAC, and several SF-36 domains. These findings suggest HILT with exercise may be more effective than SWD with exercise in managing stage 2–3 knee osteoarthritis.