Abstract: Under the condition that the traction power does not exceed 6 000 kVA, the effective avoidance distances of geomagnetism, geoelectric field and georesistivity for electrified railway transportation system are given respectively in the current 2004 edition of the national standards for seismic observation. The maximum traction power of Beijing—Shanghai high-speed railway is 19 200 kVA and there are many differences between the operation system of Beijing—Shanghai high-speed railway and the general electrified railway. Due to the progress of instrument manufacturing technology and the rapid development of national economy, the precision of instruments used and the background noise of testing sites have also changed greatly. Although the experimental criteria tested many years ago is of reference significance, it is difficult to select and construct sites according to this criterion. In this study, the Beijing—Shanghai high-speed railway is selected as the test object to carry out field observation experiments. Through analysis and calculation, the influence of Beijing—Shanghai high-speed railway operation on geoelectric field observation with respect of effective distance, interference pattern and spectrum characteristics is obtained.