Abstract: Objective 　To study the expression between tumor suppressor gene PTEN and IGF ⅠR in gas2 t ric adenocarcinoma, and to investigate the relationship between PTEN and IGF ⅠR and their connection with clinical pathological characteristics. Methods 　The expression level of PTEN and ICF ⅠR was de2 tected by immunohisto chemical SP technique in tumor and adjacent normal tissues of 60 patient s with gast ric adenocarcinoma. Results 　The positive rate of PTEN in tissues of 60 cases with gast ric adnocarci2 noma was 47. 1 %, which was significantly lower than that in adjacent normal tissues ( P = 0. 001) . The expression level of PTEN had no correlation with age and sex ( P > 0. 05) but it was significantly related to the extent of histological differentiation ( P = 0. 009), the depth of tumor invasion ( P = 0. 001), lymph node metastasis ( P = 0. 004) and clinical stage ( P = 0. 002) . There was significantly negative correlation between PTEN and IGF ⅠR expression ( rs = - 0. 469, P < 0. 001) . Conclusion 　The lost activity of tumor suppressor PTEN was closely related to the biological behavior of carcinoma of stomach. PTEN may cont rol the expression of IGF ⅠR. PTEN and IGF ⅠR can serve as the markers in the diagnosis, t reatment and prognosis of gast ric adenocarcinoma.