While the popularization of electronic transactions brings convenience to users, privacy protection and security problems exposed in transaction payment are also facing challenges to varying degrees. Aiming at this problem, we propose a secure electronic transaction protocol. The optimized signcryption algorithm in the protocol can secure safe electronic transaction. Meanwhile, payment service providers have the function of deanonymity, which can claim responsibility on the premise of protecting user privacy. Performance analysis show that the proposed protocol  can improve communication performance, meet the need of confidentiality and nonrepudiation of information, and guarantee the anonymity and traceability of buyers and fairness of electronic transactions.