The present invention provides an assistant apparatus for surmounting a barrier, which comprises a carrier body, an assistant mechanism, and a sensing/driving apparatus. The assistant mechanism, disposed at a side of the carrier body, having an assistant block disposed at the end thereof, functions to place the assistant block on the ground between the carrier body and the barrier so that the carrier body is capable of surmounting the barrier through the assistance of the assistant block. The sensing/driving apparatus, coupled to the assistant mechanism, functions to drive the assistant mechanism to generate the adjusting movement according to whether the barrier is detected or not. By means of the design of the present invention, the assistant block is adopted to reduce the height surmounted by the carrier each time so that the carrier is capable of surmounting the barrier section by section.