The invention discloses a power assisting device for climbing. The device comprises a shoe sole, a shoe support, a power supply, an electric cylinder, a control module and a touch switch. A front plate protrudes upwards from the front end of the shoe sole, and the upper end of the front plate is movably connected with the front end of the shoe support through a pin shaft. The shoe sole is provided with a shoe sole hinged support. One end of the electric cylinder is movably connected with the shoe sole through a shoe sole pin shaft. An electric cylinder rod is arranged at the other end of the electric cylinder. The shoe support is provided with a shoe support hinged support. The electric cylinder rod is movably connected with the shoe support through a shoe support pin shaft. The touch switch is arranged on the lower surface of the shoe sole. When a person wearing the device climbs stairs or a slope, the shoe sole of one foot makes contact with the ground to switch on the touch switch, and then the control module sends out a signal to enable the electric cylinder rod of the electric cylinder to extend so as to make the rear portion of the shoe support rise gradually; when the foot is lifted up, the touch switch is switched off, and the control module enables the electric cylinder rod of the electric cylinder to be shortened, so as to make the rear portion of the shoe support fall gradually to recover to the original state; in this way, physical strength is saved a lot when people climb stairs or a slope wearing the device, as the device can make climbing as easy as walking on the flat ground.