Exercise has potential to mitigate morbidity in knee osteoarthritis (OA). Participants with knee OA were randomized to a Square-stepping Exercise (SSE) group (2x/week for 24 weeks) or a control group. We assessed the feasibility of SSE and its effectiveness on symptoms (WOMAC), balance (Fullerton), mobility, and walking speed at 12 and 24 weeks. The SSE group had a 49.3% attendance rate and trended toward improvement in the 30-second chair stand at 12 (F = 1.8, p = .12, ηp2 = 0.16), and 24 weeks, (F = 3.4, p = .09, ηp2 = 0.18), and walking speed at 24 weeks, compared to controls. There were no differences in symptoms or balance. The low attendance and recruitment demonstrated limited feasibility of SSE in adults with knee OA. Trends suggest the potential for SSE to improve lower extremity functional fitness and walking speed. SSE should be further studied for effectiveness on symptoms and balance, in addition to improving feasibility.