The invention discloses a slag extruding machine of a sisal hemp leaf slag-juice separation production line. The slag extruding machine is characterized in that a feeding port is formed in one end ofthe top of a water extruding tank, the other end of the top of the water extruding tank is provided with a discharging port, a partition plate located between the feeding port A and the discharging port in the water extruding tank divides the water extruding tank into a water extruding groove and a slag discharging groove, a water extruding pipe is fixedly connected in the water extruding groove,the pipe wall of the water extruding pipe is a mesh plate with a plurality of water filtering holes uniformly distributed, a notch is formed in the position, correspondingly located below the feedingport A, of the top of the water extruding pipe to form a feeding port B, a slag extruding roller is rotationally connected into the water extruding pipe, a water extruding plate of a spiral structureis arranged on the surface of the slag extruding roller in the axial direction of the slag extruding roller, and a liquid discharge port is formed in the position, on one side of the water extruding groove, of the bottom of the water extruding tank. According to the structure, the slag extruding machine of the sisal hemp leaf slag-juice separation production line has the effects that by means of the mechanical extrusion force, leaf pulp is extruded, so that juice in the leaf pulp is extruded as much as possible, then the recovery amount of the sisal juice is improved, and the extruded slag canbe further collected.