The invention belongs to the field of chemical fertilizer production equipment, and in particular relates to an energy-saving fertilizer granulator, which comprises a work box, a base, a controller and a pillar. The controller controls the automatic operation of the granulator. An extrusion module is disposed in the work box. The extrusion module comprises a motor, a rotating roller, No. 1 slidingblocks, a sliding shaft, a No. 2 sliding block, a pressing rod, a balancing weight and a guide rail, wherein the sliding shaft is horizontally mounted on the inner roof of the work box; two No.1 sliding blocks are slidably connected to the sliding shaft; the No. 2 sliding blocks are both hinged to the No.2 sliding block through a connecting rod; the No.2 sliding block is slidably installed in theguide rail, which is fixedly installed on the bottom of the work box; and the balancing weight is hinged between the two No.1 sliding blocks through two struts. According to the invention, a materialis extruded through the extrusion module, and the chemical fertilizer granules are dried by using heat generated by the motor. Thereby, energy is saved, and production efficiency of the chemical fertilizer granules is improved.