The utility model discloses an auxiliary sharpening machine for electrode caps. The auxiliary sharpening machine comprises a supporting mechanism, a clamping and discharging mechanism, a grinding mechanism, a push mechanism, a protecting mechanism, a colleting mechanism, a body air channel controller and a sharpening motor controller, wherein the clamping and discharging mechanism is used for clamping the electrode caps, the grinding mechanism is used for grinding the electrode caps on the clamping and discharging mechanism, the push mechanism is used for pushing the clamping and discharging mechanism to move towards the grinding mechanism. The push mechanism comprises a guide rail, a connecting plate and moving parts. The body air channel controller and the sharpening motor controller are fixed on the lower portion of a grinding rack, so that the connecting plate can interfere with the body air channel controller and the sharpening motor controller respectively. The auxiliary sharpening machine is simple in structure and convenient and rapid to install and maintain, the push mechanism and the grinding mechanism are in close fit and work in linkage, compared with traditional grinding by suspension type spot welding machines, the grinding efficiency is greatly improved, only one person is used for operation, and the manpower is greatly saved.