The invention relates to an auxiliary side traveling mechanism, in particular to an auxiliary side travelling mechanism for increasing the traction of a tunnelling machine. The auxiliary side traveling mechanism solves the problems that the traction and the machine stability of the tunnelling machine are insufficient, and the like in the process of tunnelling a tunnel with heavy gradient. The mechanism is provided with an auxiliary side traveling part and a connecting buffering device, wherein the auxiliary side traveling part is fixed on the connecting buffering device and is fixedly connected with the tunnelling machine by the connecting buffering device. When the tunnelling machine works in the tunnel with heavy gradient, the traveling part can not provide sufficient traction so that the tunnelling machine can not work in the tunnel with heavy gradient, and at the moment, the auxiliary side traveling mechanism is needed to provide the traction to enable the tunnelling machine to complete the tunnelling work in the tunnel with heavy gradient. When the tunnelling machine tunnels the tunnel with heavy gradient, the traveling mechanism of the side can be adhered to the side wall ofthe tunnel so that the tunnelling machine obtains sufficient traction and good machine stability, thereby greatly improving the tunnelling efficiency and satisfying the requirements of the tunnellingmachine in the process of heavy gradient tunnelling.