目的：评价CT对腹腔和腹膜后肿瘤的诊断价值。材料和方法：回顾性分析经手术、病理证实的原发于腹脏腹源腔器外和腹膜后巨大肿瘤14例的CT表现。结果；CT对上述肿瘤的定位正确率为78．5％，良恶性鉴别的正确率为85．7％。结论：CT值可确定囊性、实性和囊实性；强化表现与肿瘤组织学有关，对部分肿瘤能揭示组织学来源；肿瘤大小对良恶性鉴别帮助不大。 Objective: To evaluate the diagnostic value of CT in abdominal and retroperitoneal tumors. Materials and Methods: The CT appearances of 14 primary tumors outside the ventral abdominal cavity and large retroperitoneal tumors confirmed by surgery and pathology were retrospectively analyzed. Results: The correct rate of CT for the above-mentioned tumors was 78.5%, and the correct rate of benign and malignant was 85.7%. Conclusion: CT values ​​can determine cystic, solid and cystic solidity; enhanced performance is related to histological histology, and can reveal histological origin for some tumors; tumor size does not contribute much to the differentiation of benign from malignant tumors.