Power line communication (PLC) is an emerging technology for multimedia, broadband Internet access and smart grid appli- cations. However, the development of PLC has been slowed down by the absence of a generally applicable channel model. The modelling of PLC channel is very challenge due to a number of reasons such as the harshness and diversity of power networks, and the difficulties in measurement. Two channel modelling approaches can be found in literature, namely the top-down ap- proach and the bottom-up approach. These two approaches are summarised and analysed in this paper. Some representative works are also presented. Several future works, including random channel generation, channel model generalisation and smart grid channel modelling are suggested.