软骨母细胞瘤大多为良性,原发恶性极为少见,我院遇1例,经手术病理证实,特报道如下。患者　男,17岁。因左胫骨上端肿痛3月入院。专科查体:左胫骨上端内侧局部肿胀,可触及边界不清的包块,约3.5ｃｍ×3ｃｍ大小,压痛明显。实验室检查均正常。Ｘ线检查:左胫骨上端可见一类圆形透亮 Most of chondroblastoma benign, primary malignant extremely rare, I hospital case of 1, confirmed by surgical pathology, especially reported as follows. Patient male, 17 years old. Left upper tibia due to pain in March hospitalization. Specialized examination: the medial upper left tibia swelling, palpable boundary ill mass, about 3.5cm × 3cm size, tenderness significantly. Laboratory tests are normal. X-ray examination: the top of the left tibia seen a class of translucent