The invention provides a radiation environment monitoring system for a nuclear power plant. The system comprises a server and a plurality of mobile terminals, wherein the server is connected to a plurality of monitoring substations of the nuclear power plant for receiving real-time data of the monitoring substations and processing the real-time data to obtain real-time monitoring data of a radiation environment of the nuclear power plant; the mobile terminals can receive and display the real-time monitoring data, so that monitoring personnel of the radiation environment of the nuclear power plant can obtain the real-time monitoring data of the radiation environment of the nuclear power plant through the mobile terminals in order to find abnormalities and carry out fast response processing,and a problem of low monitoring reliability of the radiation environment in the prior art is solved.