The invention relates to a two-way transmission control system of a vehicle. A road recognition device acquires the image of a road on which the vehicle runs currently, and according to the image of the road, after the type of the road on which the vehicle runs currently is recognized, a corresponding first terrain mode request signal is forwarded to a full-terrain controller through a signal forwarding device so as to start corresponding terrain modes in a full-terrain adaptation mode; on the other hand, the terrain controller forwards terrain mode execution information to the road recognition device through the signal forwarding device so as to achieve state feedback on a currently executed terrain mode. The problem that the information transmission rate between a full-terrain control system and an input system of the vehicle is inconsistent can be coordinated, and achievement of real-time switching among various terrain modes is facilitated.