The invention provides an organic-inorganic fertilizer granulator. The organic-inorganic fertilizer granulator comprises a roller, a first fixed drum, a second fixed drum and a stirring granulating shaft, wherein the first fixed drum and the second fixed drum are connected at the two ends of the roller; the stirring granulating shaft runs through the second fixed drum and the roller; a gear ring is fixed on the outer wall of the roller and is connected with a transmission gear on a motor; a discharge hole is formed in the roller; an air inlet, a feed pipe and a support plate are formed in the first fixed drum; a hole is formed at the center of the support plate and a bearing is installed on the support plate; a bearing and an air outlet are formed in the second fixed drum; one end of the stirring granulating shaft is rotatably connected in the bearing on the support plate and the other end is rotatably connected in the bearing on the wall of the second fixed drum; the tail end, extending out of the second fixed drum, of the stirring granulating shaft is connected with the motor; a spiral granulating blade is arranged on the surface of the stirring granulating shaft. The organic-inorganic fertilizer granulator has the beneficial effects that the organic-inorganic fertilizer granulator has the effects of shortening the production cycle and saving the floor area of equipment and energy and can save energy by more than 40-50% compared with existing granulators of the same kind and drying machines.