The invention provides a novel sludge curing treatment agent. The curing treatment agent comprises a curing agent A and a curing conditioner B, wherein the curing agent A comprises the following components in percentage by weight: 40-60% of MgO, 5-20% of magnesium chloride salt, 10-20% of SiO2, 10-30% of CaO, 0.1-4% of dehydrating agent and 0-20% of fly ash; the curing conditioner B comprises the following components in percentage by weight: 20-40% of H3PO4, 30-50% of NH4H2PO4 and 20-40% of oxalic acid; the curing agent A accounts for 0.5-10% of the total amount of sludge in treatment by mass; and the curing conditioner B accounts for 0-5% of the total amount of sludge in treatment by mass. By adopting the sludge curing treatment agent provided by the invention to treat the sludge with relatively high water content and particularly water content over 80%, the sludge can be cured generally in 1-2 days, the curing time is short, and the water content is reduced to about 30% 7 days later; after the curing, the water content of the sludge is low; and the sludge after the curing treatment can be subjected to landfill on site or applied to roadbed, greening, earthing, ecological restoration and the like, thereby avoiding secondary pollution to environment.