Abstract: Objective : To investigate the clinical and pathological characteristics of colorectal gastrointestinal stormal tumors (GISTs), and to evaluate the correct diagnosis and reasonable treatment of this disease. Methods : The clinical pathologic data and CD117, CD34 immunohistochemical of 13 eases with colorectal GIST in the late 8 years were studied retrospectively. Results : The diagnosis of 13 cases were a identified by surgery and pathology. Four of these cases were resected for eleven times in total. Most of colorectal GISTs were spindle cell type (92.3%) 92.3% of them were positively stained by CD117, and 77% by CD34. The volume of tumors were over 10cm. Mitotic rates were over 5 per HPF in 6 cases, 2 of these patient complicared with liver metastasis and 2 with bladder & peritoneum metastasis. conclusion : Volume over 10cm, mitotic rate over 5/10HPF in the potential signals for liver or other organ metastasis. Reasonable initial treatment include complete resection of the tumor and prophylactic peritonectomy, is the most effective treatmeat of the colorecal GISTs.