Human factor is important to power system operation reliability and getting increasing attention. However, the lack of method and data in human reliability analysis (HRA) is becoming an important reason for preventing the development of HRA in power system. In allusion to the status of HRA in power systems, this paper proposes an expanded cognitive model and PIFs hierarchy related to power system operation. Then a database system of human factor in power system is established, which has functions of data collection, data management, human error probability (HEP) calculation, and data sharing. Results show that the database system can provide data support for verifying the applicablility of existed HRA method for power system operation and developing new HRA method. This work is supported by National Natural Science Foundation of China (No. 51537010) and National High-tech R & D Program of China (863 Program) (No. 2015AA050204).