Increased life expectancy in several populations makes osteoarthritis (OA) an important public health issue, as it is a very prevalent chronic disease and leading cause of pain and disability among adults and elderly. Objective: The aim of this study was to compare pain, mobility, functional capacity, and strength of patients with knee osteoarthritis submitted to two different interventions: resistance exercise (REG) and kinesiotherapy (KIG). Methods: This was a prospective randomized single blind clinical trial, which involved the participation of 30 adults of both sexes diagnosed with knee OA. Volunteers were evaluated for pain, stiffness, function, functional mobility, and strength by a blinded evaluator before and after the interventions. Through a simple drawing, participants were randomly assigned to one of the two intervention groups, and underwent 15 twice-weekly treatment sessions, lasting 30 minutes each. Results: Both interventions promoted significant improvements in all variables, and there were no reports of any adverse effects throughout the research. Conclusion: Both resistance exercise and kinesiotherapy are effective in improving pain, stiffness, function, functional mobility, and strength in patients with knee OA.