The invention discloses an efficient heavy metal sludge treating agent. The efficient heavy metal sludge treating agent is prepared from, by weight, 5-12 parts of glutamine, 25-35 parts of sodium bentonite, 5-10 parts of methylparaben, 10-20 parts of activated carbon, 5-8 parts of polydiallyldimethylammonium chloride, 2-8 parts of p-chloromethyl benzoic acid, 2-6 parts of 2-aminopyridine-4-methanol, 5-12 parts of biogas residues, 5-10 parts of waste culture media for edible fungi, 2-4 parts of degrading bacteria, 10-20 parts of bentonite and 0.2-0.4 part of ferrous sulfate. Physical and chemical indicators of soil heavily contaminated by heavy metals can reach the GB15618-2008 standard; the treatment technology is simple, the dosage is small, the treatment effect is good, the performance is stable, the contaminated soil recovery degree is high, the cost of the treating agent can be effectively lowered, and the treating agent has good economic benefits and extensive social benefits.