A rotary drum type sludge thickening and dewatering machine for 
sludge treatment, comprising a separation cylinder, wherein a stirring component is provided inside the separation cylinder, a rotary drum is provided on one side of the separation cylinder, and the separation cylinder is connected to the rotary drum through a connecting pipe. The interior of the rotary drum is provided with a spiral rotating extrusion dehydration component, which is used for sludge thickening and dewatering. The side wall of the rotary drum is provided with a leakage hole, and the side of the rotary drum away from the separation cylinder is provided with a discharge port. Through the cooperation of the separation cylinder and the stirring component, the sludge is dispersed to prevent pipeline blockage, and the free water in the sludge is preliminarily separated. Then, the spiral extrusion component compresses and dehydrates the sludge in the rotary drum through extrusion. By combining two separation methods, the sludge can be deeply separated. Concentrated dewatering improves the efficiency of sludge dewatering.