This paper examines the relevant legal system and integrates blockchain technology to ensure network information security protection at multiple levels, thereby meeting the requirements for network information security protection. The network information security protection effect of blockchain technology and initial technology is compared and analyzed. Subsequently, experiments such as SM2 encryption algorithm performance testing and analysis, anti-DDOS attack experiments, and anti-interception tests are conducted to prove the effectiveness and feasibility from the experimental point of view. The experiments reveal that the blockchain network information security protection test group always has a response time below 0.3s, resulting in higher protection efficiency. Compared to the RSA algorithm, the SM2 algorithm shows a shorter key length, which is more secure and efficient. The 2KB data encryption and decryption of the SM2 algorithm consume no more than 82.6 ms and 55 ms, respectively. With the increase in the attack rate, the transmission time of the DDOS attack detection mechanism fluctuates less, tends to be stable, and has excellent covertness, anti-attack, and transmission performance. This paper’s scheme satisfies the legal requirements, guaranteeing the highest level of data protection.