With the popularity and promotion of blockchain technology，blockchain applications have sprung up like mushrooms，and there are many good blockchain applications that are affecting and changing the way we produce and live. This report first introduces the related technology of the existing information system in the field of security and privacy protection，and then analyzes the relevant technical principles of information security and privacy protection layer by layer from the perspective of the five-layer technology architecture of the blockchain，and explains how to construct a secure and reliable blockchain application system. Finally，combined with quantum cryptography technology，the threat to the privacy and security of blockchain is discussed，and the necessity of anti-quantum cryptography technology development is prospected.