The invention relates to the technical field of braking, and provides an auxiliary braking device and an electric balance wheelchair including the auxiliary braking device. The auxiliary braking device comprises a mounting frame, a power assembly, one or more motion members, one or more first braking assemblies, and one or more second braking assemblies, wherein the motion assemblies can be movably connected to the mounting frame and connected to the power assembly; the first braking assemblies are correspondingly connected to the side surface of an end departing from the mounting frame, of the motion members, and each first braking assembly comprises a truckle and a friction plate cooperating with the corresponding truckle; the second braking assemblies are correspondingly connected to the bottom surface of the end departing from the mounting frame, of the motion members, and comprise friction blocks; the motion members are driven by the power assembly to drive the first braking assemblies and the second braking assemblies to depart from the mounting frame and move relative to the mounting frame, the truckles are in contact with the ground at the first time, then at the second time, the friction plates go downwards to be in contact with the truckles, and at the same time, the friction blocks go downwards to be in contact with the ground. According to the electric balance wheelchair disclosed by the invention, the braking distance is short.