Abstract:Only six certificateless signcryption schemes have been proposed in recent years. Most of them cannot provide confidentiality and authentication. Even if some of them are secure, all of them need pairing operations. In order to solve the above-mentioned problems, a pairing-free certificateless signcryption scheme is proposed, and its security has proven to be in the random oracle model (ROM) under the computational Diffie-Hellman (CDH) assumption and the hardness of discrete logarithm problem (DLP). This scheme eliminates pairing operations and is the most efficient certificateless signcryption scheme.