Disclosed are a method for producing an aripiprazole suspension, wherein the aripiprazole has a mean particle size of 1 to 10 μm, the method comprising the steps of: (a) combining bulk aripiprazole and a vehicle to form a primary suspension； (b) subjecting the primary suspension to first pulverization using e.g., a high shear pulverizing machine, a dispersion machine that applies shear force to a material to be processed, a colloid mill, an ultrasonic dispersion machine, or a high-pressure jet type emulsifying dispersion machine to form a secondary suspension； and (c) subjecting the secondary suspension to second pulverization using e.g., a high-pressure jet type emulsifying dispersion machine to form a sterile final suspension； and a method for producing a freeze-dried formulation from the aripiprazole suspension.
