This study investigated the effect of health belief model-based educational intervention on nutritional function of rural women with stomach cancer in the city of Talesh in 2017. It was a randomized controlled field trial, performed in several stages. The first phase of sampling used simple random sampling method and the second phase used systematic random sampling method. Data were collected using a four-section questionnaire, including: demographic information, knowledge assessment, health belief model constructs and performance measurement. Inclusion criteria included: willingness to participate in the program, women aged between 18 and 60 years, no history of stomach cancer in the subjects, their spouses or their first-degree female relatives and being literate. Exclusion criteria included: quitting training sessions and changing the respective center. The informed written consent was obtained. Based on the results of the first stage, the predictive constructs, appropriate educational methods and studies conducted by the author and the co-author, the educational intervention was conducted in six 40-50 minutes sessions, using the following methods: lecture, participatory and activation methods, question and answer session, group discussion and brainstorming method.