In view of the extremely complex environment of the nuclear accident site and the high radiation level, manual direct entry for monitoring and inspection has great safety risks, and it is difficult to meet the actual needs in terms of efficiency and accuracy. In this paper, an intelligent mobile car equipped with X and γ radiation dose rate module is proposed to solve the above problems in an automatic and intelligent way. The mobile vehicle integrates advanced nuclear radiation sensors, high-precision three-dimensional Lidar, monocular or multi-ocular cameras and intelligent motion control systems, which can autonomously navigate or remotely operate in the complex and changeable nuclear radiation environment to achieve real-time and accurate measurement of nuclear radiation dose rate. By integrating these data, the vehicle can dynamically build and refresh the radiation dose point cloud map in real time, providing workers with intuitive and comprehensive radiation environment distribution information. In order to verify the effectiveness and feasibility of this method, tests were carried out in simulated nuclear radiation environment and real nuclear industry site. By comparing the data of measurement field with the high-precision simulation model, not only the accuracy of radiation dose measurement is confirmed, but also the stability and reliability of this method in the complex radiation environment is demonstrated.