With the development of blockchain technology and the increased demand for its application in e-commerce. However, the encryption algorithm of traditional blockchain technology poses a risk to data security protection. Therefore, this paper builds secure cryptographic protection by means of secondary encryption and interactive verification of the interaction process of e-commerce transaction data through a hash function. Then, for the transaction process of e-commerce, an electronic transaction protocol with privacy protection is proposed. The effectiveness of blockchain-based e-commerce transactions is analyzed according to correctness and security. The questionnaire of this study has good reliability based on the analysis of relevant data, where the overall reliability of all variables is 0.865. There is a positive correlation between the efficacy of e-commerce transactions and correctness, anonymity, resistance to simulation attacks, and accountability protocols at the 5% significance level. The correlation between traceability, non-repudiation, and resistance to replay attacks is not significant. E-commerce transaction effectiveness = 0.326* correctness + 0.455* anonymity + 0.354* traceability + 0.254* non-repudiation + 0.171* resistance to simulation attacks + 0.445* resistance to replay attacks + 0.552* accountability protocol. The accountability protocol factor has the greatest impact and contribution to the e-commerce transaction effectiveness of blockchain.