The invention discloses a method for keyword searchable encryption based on bilinear pairs in cloud storage. The method includes the steps that firstly, system parameters are initialized; users are added; thirdly, encryption and security indexes for files are generated; fourthly, search tokens, relative to keywords, of the users are generated; fifthly, a cloud storage server is searched for keywords relative to ciphertexts; sixthly, the ciphertexts are decrypted by the users; seventhly, the users are logged out. According to the method, the authorized users can look for the encrypted files through a trap door connected with the keywords. The keywords used by the users for search cannot be known even by the cloud storage server, so that security of user information can be guaranteed; Compared with an existing scheme, the comprehensive efficiency of the aspects of communication and calculation cost, namely the aspects of the search speed of the size of the trap door, the encryption and search speed of the keywords, of the provided scheme is improved, and the method is suitable for multi-user environments.