Abstract: To establish and improve the cryptographic guarantee system for China Railway Ticketing and Reservation System (abbreviated as the ticketing system), optimize cryptographic infrastructure, advance the application of cryptographic technologies in ticketing business, and satisfy the national commercial cryptography application security assessment requirements, this paper proposes an architectural design method for the cryptographic guarantee system of the ticketing system. Adopting layered abstraction, function isolation and standardized engineering technologies, this paper constructs a cryptographic infrastructure support platform, a cryptographic application support platform and a cryptographic operation guarantee platform. Adopting cryptographic resource pool management and cryptographic resource scheduling technologies, the system realizes unified management and dynamic scheduling of cryptographic devices as well as elastic service expansion, and provides secure, compliant and user-friendly cryptographic resources and services for business applications. Practical verification shows that the proposed cryptographic guarantee system supports collaborative cryptographic security services, reduces development, operation and maintenance costs, and comprehensively enhances the information security protection capability of business application systems.