Background and Objective: The planning of educational programs to inform the people about the prevention of diseases such as cancers is necessary. With considering the high incidence and mortality rate and costly and difficulty screening of gastric cancer in Iran, this study was conducted to determine the effect of educational interference based on HBM on knowledge, attitudes and practices of housewives about nutritional factors associated with gastric cancer. Materials and Methods: In this quasi experimental study, 84 of housewives from Isfahan participated and were randomly categorized into two groups (experimental and control groups). Before the performing of educational program based on HBM, the self-structured, valid and reliable questionnaires were completed by the groups. Then, the experimental group received the educational program about the correct nutritional behaviors in the form of lecture, group discussion and questioning and answering in 4 sessions and the non-intervention group did not receive the education. Both groups completed the questionnaires 2 months after the intervention. Data were analyzed using SPSS18 by Mann-U- Whitney, t student and paired t test and p < 0/05 considered significant. Results: The mean age was 34.11 ± 6.23 in intervention group and 34.21± 6.5 years in non-intervention group and the difference was not significant. There was not also a significant difference in knowledge, perceived susceptibility, perceived severity, perceived benefits, perceived barriers, perceived self- efficacy and practices of women before the intervention (p < /span>>0.05), but difference was significant after the intervention (p < 0.001). Conclusion: Health education based on HBM increases the knowledge and improves the attitudes and practices of housewives women with regard to nutritional factors for prevention of the gastric cancer.