The invention discloses an auxiliary platform for testing a lightning arrester leakage instrument and belongs to the technical field of power equipment. According to the auxiliary platform, the technical problem that the lightning arrester leakage instrument cannot be positioned in a horizontal state during testing is solved; the auxiliary platform for testing the lightning arrester leakage instrument, disclosed by the invention, comprises a platform body and adjusting screws arranged at four corners of the platform body; a leveling instrument is arranged on the platform body; a clamping device for clamping the lightning arrester leakage instrument is also arranged on the platform body.