Abstract: Objective To evaluate the validity and relability of the gastric cancer influcing factor questionnaire.Meth ods The gastric cancer influcing factor questionnaire was established with literature review,investigation and consultation.To tally 351 stomach cancer patients and healthy person were investigated with the que stionnaire.Cronbachs' alpha coefficient, spit-half coefficient,content validity,discrmi inatory validity and construct validity were adopted in the data analysis with SPSS 131 0.Results The cronbachps Acoefficients of all dimensions of the influcing factors tested ranged from 0.7430-0.8763, and the spit-half coefficient was 0.71.All the in ternal consistency Cronbachps coefficients were above 0.70.The correlations between the item and other domains were low,and were lower than the correlations between the doma in and other domains. Factor analysis resulted in unid miensional pattern,which supported the use of a total score.Conclusion The gastric cancer influcing factor questionnaire has good reliability and validity and can be applied in field epidemiologic study of stamach cancer.