Urban railway transit rail to earth transition resistance testing system and method

The invention relates to an urban railway transit rail to earth transition resistance testing system and method. A conventional urban railway transit rail to earth transition resistance testing system cannot meet requirement of on-site tests for low power and high precision. The urban railway transit rail to earth transition resistance testing system comprises a testing system host machine and a far end data collection and transmission device that are connected with each other for information interaction; the testing system host machine comprises a programmable control low power current source, an automatic control module, a digital type high precision voltage measurement and storage module I, a wireless communication module I, a data processing module and a man-machine interaction module; the far end data collection and transmission device comprises a device automatic control submodule, a digital high precision voltage measurement and storage module II and a wireless communication module II. The portable pro