Clinical data, pathological histology, immunohistochemistry, tumor risk assessment and survival status analysis were used to analyze the clinicopathologic features and biologic behavior of primary extragastrointestinal stromal tumors. There were 5 patients with extragastrointestinal stromal tumour (EGIST), 2 males and 3 females, with an average age of 53 years. The original sites of the tumor were omentum, retroperitoneum, groin, rectovaginal septum and the average diameter of the tumor was 12.6 cm; spindle type were 3 cases, epithelioid type was 1 case and mixed type was 1 case; 2 cases of mitotic index more than 10/50 HPF, 2 cases more than 5/50 HPF, 1 case less than 5/50 HPF, 2 cases with tumor rupture, 3 cases with tumor necrosis, 5 cases with CD117 positive, 5 cases with DOG1 positive, 3 cases with CD34 positive. Five cases of tumors were all high risk, 3 cases of recurrence/metastasis, 1 case of disease survival, 2 cases of disease-free survival; the average over survival time was 40.2 months. Extragastrointestinal stromal tumor is a rare tumor, it can be found in the rare part of the inguinal soft tissue. The average diameter of the tumor is more than 10 cm, which is mostly high risk and the risk of recurrence/metastasis is high. The histology type is mainly spindle cells, CD117 and DOG1 are helpful for the diagnosis of extragastrointestinal stromal tumors.