The invention belongs to the technical field of fast reactors and discloses a process and a system of cleaning and removing sodium. The process comprises the steps of creating inertia environment, lifting to-be-cleaned equipment, pre-heating a system, cleaning with water vapor, cleaning with water, drying, and treating and discharging cleaning liquid waste. The system mainly comprises a liquid nitrogen low-temperature storage tank (1), an electric vapor generator (2), a cleaning tank (3), a liquid waste collecting tank (6), a hydrogen analysis meter (10), a water vapor condenser (7) and a gas-water separator (9). The process and the system of cleaning and removing the sodium can avoid explosion hazards, prevent overheating of the surface of structural materials, and clean the sodium remaining in the equipment effectively and rapidly.