In order to obtain the flux density and distribution characteristic of the power frequency magnetic field (PFMF) transmitted into the carbodies through windows of different electrified trains, the PFMF measurement data from high-speed, motor and ordinary cars were analyzed by GB/T24338 (Railway Applications Electromagnetic Compatibility). According to characteristics of traction power supply and carbody structure of electrified trains, a model for calculating the power frequency magnetic flux density from car windows was established, and the calculation results of the model were compared with the practical measurements to verify its effectiveness. The results show that the magnetic flux distribution obtained by the proposed theoretical model is consistent with the measurement data, and there is a positive correlation between the PFMF transmitted through vehicle windows and the traction current. The error between calculated results and measurements is within±5%, which verifies the validity of the model.