The invention discloses a ground driving mechanism suitable for transferring a piggyback transport car. The ground driving mechanism comprises a supporting component, a moving component and a power device; the supporting component is fixed to the ground and is provided with a first track matched with the motion trail of a tray; the moving component is provided with a second track matched with the first track in the motion process, and a matching part capable of being connected to or separated from the tray is arranged at the end, opposite to the tray, of the moving component; the power device drives the moving component to move along the first track in a reciprocating mode. The ground driving mechanism driving the tray for a railway vehicle to move is arranged on the ground, and therefore the self weight of the piggyback transport car can be greatly lowered, the coefficient of the self weight of the car is small, the whole performance parameters of the railway vehicle are greatly optimized, the structure of the railway vehicle is simplified, and the performance reliability of the railway vehicle is improved. The ground driving mechanism driving the tray for the railway vehicle to move is arranged on the ground, and therefore the use cost of the piggyback transport car can be lowered. In addition, the ground driving mechanism is more flexible and convenient to arrange.