目的　探讨超声在腹膜后原发性肿瘤的诊断价值。方法　本文对经手术病理确诊的 2 9例腹膜后原发性肿瘤的声像图特征与病理类型进行回顾性对照分析。结果　超声检出率及定位诊断符合率 89 7%(2 6 / 2 9例 ) ,良性肿瘤 16例 ,其中囊性肿块 6例 ,以液性为主的混合性肿块 5例 ,低回声实质性肿块 4例 ,实质均质性肿块 1例。恶性肿瘤 13例 ,其中呈实质不均质性肿块 8例 ,实质均质性肿块 1例 ,以实质为主的混合性肿块 4例。结论　超声检查有助于腹膜后原发性肿瘤良恶性的鉴别 ,并有助于评价肿瘤与周围脏器之间的关系 ,对指导临床手术治疗提供重要的参考价值 Objective To investigate the diagnostic value of ultrasound in primary retroperitoneal tumors. Methods In this paper, 29 cases of retroperitoneal primary tumors confirmed by surgery and pathology were retrospectively analyzed with sonographic features and pathological types. Results The coincidence rate of ultrasound detection and localization was 89.7% (26/29), 16 cases of benign tumor, 6 cases of cystic mass, 5 cases of mixed liquid mass, low hypoechoic mass 4 cases of lumps, 1 case of homogeneous lumps. Thirteen cases of malignant tumors, including 8 cases of substantially inhomogeneous mass, 1 case of homogeneity mass, 4 cases of mass-based mixed mass. Conclusion Ultrasonography is helpful to differentiate benign and malignant retroperitoneal tumors and to evaluate the relationship between the tumor and the surrounding organs. It provides an important reference value for directing surgical treatment