Objective:To explore the correlation of sex hormones concentration,ER receptor,and the polymorphism of ERβ gene with the development of gastric adenocarcinoma in young people. Methods:Two hundred and sixteen cases of primarily gastric adenocarcinoma in young people and 160 cases of gastrohelcoma surgery patients were analyzed. Radioimmunoassay(RIA) was used to determine the levels of sex hormone. Immunohistochemistry method was used to detect the expression of ER. Polymerase chain reaction-restriction fragment length polymorphism method was used to detect the polymorphism of ERβ of test group. Results:Serum androgenic hormone levels were significantly lower in the control group than that of the test group,but serum estradiol levels were higher in the control group than that of the test group. No significant difference can be seen in the TNM staging in the test group between male and female. But androgenic hormone levels decreased progressively,estradiol levels increased progressively with differentiation degree degraded,and there are significant difference between positive and negative lymph node metastasis. There was negative expression of ERα and ERβ in control group. The positive rate of ERα and ERβ in the test groups were 57.4%(124/216) and 15.7%(34/216). The positive rates of ER were significantly higher in the tissue with lower differentiation degree,having lymph node metastasis and deeper infiltration degree than that with higher differentiation degree,having no lymph node metastasis and shallower infiltration degree. Moreover,the positive rates of ER were higher in the stage of TNM Ⅲ than in the stage of TNMⅠandⅡ. RR and Rr genetype rate were higher than rr genetype rate. RR genetype was most obviously observed by PCR-RFLP with the allelomorphic gene distribution of RsaI. RR were significantly higher in the tissue with lower differentiation degree,having lymph node metastasis,deeper infiltration degree,and with the stage of TNM Ⅲ than that with higher differentiation degree,having no lymph node metastasis,shallower infiltration degree,and with stages ofⅠandⅡ. There was no significant difference in all genetypes with the allelomorphic gene distribution of Alu I in the test group. Conclusion:The alteration of sex hormones concentration in serum is one of important factors effecting the cancerization of gastric gland. The polymorphism of ERβ gene may be related to the development of gastric carcinoma.