The aim of this study is to determine the effect of education based on health belief model in promoting behaviors of vitamin D deficiency among Middle School Girl Students in Arak city . (Inclusion Criteria: Students who like to participate in the study and have informed consent of them and their parents; they study in government schools.)(Exclusion criteria: the absence of a training session or moving from her school to another school for any reason; under special diet.)The population consists of 140 Middle school girls, In the beginning, randomly from four school from districts 1 and 2 Arak were selected .The number of each groups were 70 people. Four educational sessions of 90 minutes hold about nutritional sources of vitamin D and using of sunlight during every day, by present education, the book and education pamphlet which this proses was hold by helping school administrators. In the end, after three months, questionnaires in this respect shall be filled by the participating students and the control group is also given the training packages which intervention group has given. The primary outcome of this study: (To determine the knowledge, perceived susceptibility, perceived severity, perceived benefits, perceived barriers, manuals and internal and external, efficacy, operation of vitamin D deficiency in promoting preventive behavior in school girl.)