Abstract: Field-to-line coupling model research is an important part of electromagnetic compatibility analysis and electromagnetic effects assessment. At low frequency, the classical field-to-line model based on quasi-TEM wave approximation can be used to calculate the current and voltage response excited by the external field. However, if the incident frequency becomes high enough that the corresponding wavelength is comparable to the transverse size of the transmission line, the classical model will produce unacceptable model error. Therefore it is necessary to develop high-frequency field-to line coupling model. This paper introduces the research progress of high-frequency field-to-line coupling models for multi-conductor transmission line. A detailed analysis and comparison of TRI model and TLST model (two main branches of high-frequency field-to-line coupling model) are given. Then the principle of the TLST model is briefly introduced and the models validity and accuracy are illustrated by a simulation example. Finally, the research contents and objectives of high-frequency field-to-line coupling model are summarized and prospected.