We aimed to review the results of subtotal arthroscopic resection of symptomatic type D medial plica. We retrospectively evaluated 23 knees with symptomatic type D medial plica in 22 patients without other intra-articular pathology. All patients complained of chronic knee pain that had not been alleviated by medical treatment or physical therapy. In only three (13%) of the patients studied was the plica diagnosed pre-operatively with magnetic resonance imaging. The type D medial plicae in our series were classified as fenestrated (14 knees), torn (5 knees), or reduplicated (4 knees). Fibrotic changes in the plicae and degenerative changes on the medial femoral condyle were found in 16 knees Patellofemoral chondromalacia was present in three knees Arthroscopic partial resection was performed in all patients. Comparative Lysholm Knee Scale scores before and after surgery revealed a significant clinical improvement (pre-operative status, 67.19 +/- 8.05 vs. post-operative status, 90.57 +/- 9.80; P < 0.001). Type D medial plica should be considered as a possible cause of chronic knee pain. Arthroscopic partial resection of the plicae in symptomatic patients gives satisfactory results.