Arthroscopy was used to diagnose and treat osteochondritis dissecans (OCD) of the femoral condyle in six dogs. Bilateral lesions were seen in two dogs. The medial condyle was affected in five stifles, and the lateral condyle was affected in three stifles. Subchondral bone defects were identified on radiographs in six of eight affected stifles. Resolution of the lameness associated with the arthroscopic procedure occurred one-to-14 days (mean, three days) following arthroscopy. Lameness resolved completely in four cases within two weeks and in one case six weeks following arthroscopy. Mild lameness persisted in one case. Arthroscopy is an effective means of diagnosis and treatment of OCD of the femoral condyle, and it is associated with minimal postoperative morbidity when compared to arthrotomy.