An in-situ regeneration device of an SCR catalyst for household garbage burning comprises an anaerobic fermentation tank, a biogas blower fan, a biogas adjusting device, a biogas desulfurization tower, a combustion fan, a hot wind furnace, a secondary air fan, a regeneration flue baffle door, an SCR reactor, an SCR catalyst, a flue collector baffle door, GGH, a wet process washing tower, an induced draught fan, and a chimney. The anaerobic fermentation tank, the biogas blower fan, the biogas adjusting device, the biogas desulfurization tower, the combustion fan, the hot wind furnace, the secondary air fan, the regeneration flue baffle door, the SCR reactor, and the SCR catalyst form a catalyst regeneration system. A wet type acid removing tower removes SOx and NH3 in regenerated flue gas,and the discharged flue gas can meet the discharge standards during the regeneration period.