By means of mobile communication technology, enterprises can more easily track users and collect their personal information. This has aroused users’ privacy concern. This paper explores the impact of privacy concern on m-commerce user acceptance behavior. Privacy concern as a second-order factor includes four dimensions: collection, improper access, information error and secondary usage. The results show that improper access and information error have relatively higher loadings on the second-order factor. Privacy concern significantly affected user risk perception and trust and through them indirectly affected behavioral intention. Thus, m-commerce enterprises should pay more attention to users’ privacy concern and take effective measures to alleviate their privacy anxiety.