Certificateless cryptography not only overcomes the certificate management problems in the traditional public key cryptosystems, but also solves the key escrow problems in identity-based cryptosystems. This paper presented a secure Certificateless signcryption scheme from pairings based on Zhang Lei et al. 's signature scheme. A security analysis proves that the proposed scheme is secure against existential forgery on an adaptively chosen message attack under the assumption of DL and CDH problems.