In spite of the much investment on using IT in banking and in spite of users’ easy access, reports show that some people do not use it. This problem shows the need to explore factors which determine the acceptance of Internet banking system by users. The purpose of this study is to establish the relationship between Perceived Security and trust in Internet Banking from the viewpoint of female customers in different Semnan branches of SADERAT BANK. This applied research has a correlational-descriptive aim. The sample included 147 female customers of this bank who answered a questionnaire its validity and reliability were checked. The research hypothesis was tested using SEM. According to the results, P.S. has a direct, significant, positive effect on the trust in I.B.