目的：性分化异常的细胞遗传学病因。方法：每例性分化异常患者取外周血淋巴细胞常规制备染色体。Ｇ带、Ｃ带，高分辨显带及银染技术分析核型。结果：１１１例性分化异常患者中检出染色体异常４５例，数量异常１４例，结构异常３１例，包括缺失、倒位、易位、环状染色体、额外小染色体等。结论：染色体异常是性分化异常的重要原因，分析患者的核型，对于诊断及治疗均有一定意义。 Purpose: Cytopathological causes of abnormal sexual differentiation. Methods: Peripheral blood lymphocytes were routinely prepared for chromosomes in each patient with abnormal differentiation. G-band, C-band, high resolution banding and silver staining techniques karyotype analysis. Results: Among the 111 patients with abnormal differentiation, 45 cases were detected chromosomal abnormalities, 14 cases were abnormal in quantity and 31 cases were abnormal in structure, including deletion, inversion, translocation, circular chromosomes and extra small chromosomes. Conclusion: Chromosomal abnormalities are the important reason of abnormal sexual differentiation. Analyzing the karyotype of patients has certain significance for diagnosis and treatment.