Changes in subchondral bone in knee osteoarthritis could be a marker of altered fluid dynamics. Perfusion can be visualized and quantified with MRI using dynamic contrast enhanced MRI (DCE-MRI). Using quantitative analysis of DCE-MRI, we compared perfusion in the affected compartment with the non-affected compartment in patients with unicompartmental knee osteoarthritis. We also evaluated the perfusion in subchondral bone marrow lesions (BMLs). Perfusion of the subchondral bone measured with DCE-MRI is not significantly different between the affected and non-affected compartment. Subchondral BMLs are significantly associated with increased perfusion parameters compared to subchondral bone regions without BMLs.