Primary relatives of individuals with breast cancer need information and support due to genetic transmission and fatal consequences of breast cancer. Aim: The purpose of this study was to translate and culturally adapt the “Information and Support Needs of the Primary Relatives of Individuals with Breast Cancer Questionnaire” (ISNQ) into Persian language. Materials and Methods: Study was carried out in Noor Nejat Hospital’s Breast Polyclinic and Radiation Oncology Department. In validity and reliability study carried out totally 145 women who had immediate relatives with breast cancer were reached. The 29-item ISNQ was translated to Persian language, back translated, and tested. In the validity studies of the scale, language, content, construct validity, reliability and time consistency and internal consistency analyzes were carried out. Results: In this study, as a result of the explanatory factor analysis, the KMO value of the scale was calculated as 0.57 in the information part and 0.70 in the support needs part. The eight factors all together explained 77.8% of the variance. It was the first factor (concerns of supporting information) explaining the biggest part of variance. In the internal consistency analysis, Cronbach’s Alpha value was calculated as 0.86 for the Information part and 0.92 for the support needs part. Conclusions: The reliability and validity of the Persian adapted version of the ISNQ was shown to be satisfactory. Thus, it can be used to investigate the information and support needs of Iranian women with first-degree relatives of breast cancer.