Background: Osteoarthritis is the most common joint disease in theworld,including Indonesia. Obesity is a risk factor that can modification tooccurance knee osteoartritis Objective: To determine the relationtionshipbetween obesity and occurrence osteoartritis of the knee in Orthopedicpolylinic of dr. Soedarso General Hospital Pontianak on 2013. Method:This research was an analytic study with cross sectional.It was conductedon Orthopedic Polyclinic with total subject were 64 peoples with chisquaretest. Results: The results obtained using the chi - square testgenerate yield p = 0.004 Conclusion: There is relationship beetweenoesity and occurrence osteoarthritis of the knee in Orthopedic polyclinic ofdr. Soedarso General Hospital Pontianak on 2013