Abstract: This paper focused on the migration, transformation, and deepening application of commercial passwords in railway business systems. Based on the analysis of typical application scenarios and security requirements of railway business systems, a systematic study is conducted on the migration methods and key technologies of railway commercial passwords. The paper proposed a migration object recognition method driven by commercial password application security assessment, and a priority division approach based on security risk level, business importance, and implementation difficulty. It elaborated on key technologies such as the adaptation of national encryption algorithms to business protocols, lightweight authentication and encrypted transmission, password resource pool and unified key management, selection of commercial password products, and hardware acceleration, providing reference for commercial password transformation and network information security protection in railway business systems.