ObjectiveTo investigate the value and feasibility of low-field MR in the diagnosis of excessive lateral pressure syndrome (ELPS) of the patellofemoral joint. MethodsThirty-seven patients confirmed to have ELPS by surgery or clinical examination between March 2010 and March 2013 were involved in this retrospective study. The injured knees of all patients were examined by SE sequence and Fat sequence, using Siemens 0.35 T MR scanner. The patella was assessed. Infrapatellar fat pad, patella tilt angle and patellofemoral joint space were measured. ResultsThere were 15 cases of type Ⅱ, 21 of type Ⅲ, and 1 of type Ⅳ knees. Three cases of bipartite were detected. Patella tilt angle: type Ⅳ > type Ⅲ > type Ⅱ. Infrapatellar fat pad had edema in 37 cases. And there were 29 cases of varying degrees of lateral patellar cartilage softening. ConclusionLow-field MRI is an effective diagnostic method of excessive lateral pressure syndrome for patellofemoral joint. STIR sequence is the best sequence for diagnosing patellofemoral excessive lateral pressure syndrome.