A slurry treatment device comprises a slurry tank, a thermal-insulating tank and a heating system, wherein the slurry tank is arranged in the thermal-insulating tank; the heating system comprises a heating tube surrounding the slurry tank; liquid oil is injected into the thermal-insulating tank and surrounds the slurry tank; the slurry tank is made of a metal material and comprises a tank body and an end cap, a slurry inlet is formed in the end cap, and a slurry outlet is formed in the lower part of the tank body. The sludge treatment device has the advantages as follows: with the arrangement of the heating device, slurry can circulate smoothly in high and cold regions; uniform heating is guaranteed through indirect heating of the liquid oil, and materials in the slurry are prevented from being denaturized and attached to a tank wall; a stirrer inlet is formed, stirring can be performed whenever stirring is required, and blocking is avoided; a gas outlet is formed in the top end, quick decompression can be realized when gas in the slurry is heated and overflows, and pressure in the tank body is prevented from being excessively high; a slurry port is formed in the lower part of the tank body and is also used as an analyzer port in a shielding system, and the concentration of the slurry in circulation can be monitored in real time.