The invention provides a chromium plating repair method and a chromium plating repair clamp for an inner circle surface of a rear journal. The inner circle surface needing chromium plating repair is formed in the middle of the rear journal; an upper inner circle surface and a lower inner circle surface are adjacent to the inner circular surface, the upper inner circle surface is positioned on the upper surface of the inner circle surface, and the lower inner circle surface is positioned on the lower surface of the inner circular surface; the chromium plating repair clamp comprises an upper screen board and a lower screen board; the upper screen board is matched with the upper inner circle surface in size and made of plastics; the lower screen board is matched with the lower inner circle surface in size and made of plastics; a center through hole for an anode bar to pass is formed in the upper screen board; a center blind hole through which the bottom of the lower screen board can be propped against the anode bar is formed in the lower screen board. The chromium plating repair clamp provided by the invention can be used for firmly fixing the rear journal to avoid non-uniform thickness of a clad layer due to position variation of the rear journal, and meanwhile, the chromium plating repair clamp is used for very conveniently and quickly covering and protecting parts which need not to be repaired through chromium plating, so that protection workloads such as painting and lead sheath sticking are reduced, the working efficiency is improved, and the repair cycle is shortened.