We investigated the morphological changes in the articular cartilage after rotational acetabular osteotomy in 16 adolescent rabbits. Radiological and histological studies were conducted at 12 and 24 weeks postoperatively. The radiological evaluations at 12 and 24 weeks showed significantly increased femoral head coverage. No cases of osteonecrosis of the acetabulum or femoral head nor narrowing of the joint space was observed. The histology of the articular cartilage at 12 weeks postoperatively showed cloning and hypercellularity of the chondrocytes in the medial portion of the acetabular roof, indicating remodelling due to the increased weight-bearing stress caused by the osteotomy. The histology at 24 weeks postoperatively showed less cloning of the chondrocytes, indicating that the remodelling process in the articular cartilage induced by this procedure was almost complete at 24 weeks. Degeneration of the articular cartilage was not observed within 24 weeks of the operation.