The invention belongs to the technical field of rail transit and specifically relates to a steep slope running assisting system. The invention aims at solving the stability problem of a train in steepslope rail running in the prior art. The steep slope running assisting system comprises two rail lines and a traction device, wherein the two rail lines are arranged on a steep slope; the traction device comprises a traction rope and a traction guiding device; the traction guiding device is arranged at high altitude; the traction rope penetrates through the traction guiding device; the two rail lines are correspondingly used for the train to run up and down; and when two trains correspondingly run along the two rail lines in opposite directions as an up train and a down train, the two ends ofthe traction rope are correspondingly connected with the up train and the down train, provide up tension for the up train and provide down resistance for the down train. According to the steep sloperunning assisting system, the stability of the train in steep slope running can be improved so that the train runs in a safe, reliable, energy-saving and consumption reducing manner.