The invention discloses a crushing stirring machine for preparing a megestrol acetate suspension. The crushing stirring machine comprises a first machine body, a second machine body, a crushing cavity, a first valve, a stirring machine body, a water tube, a discharge mechanism, a second feeding hole and a base, wherein a first motor is arranged inside the first machine body; a first rotating shaftis arranged below the first motor; crushing blades are fixed on the outer side of the first rotating shaft; the second machine body is arranged below the first machine body; the crushing cavity is formed inside the second machine body; crushing blades are arranged inside the crushing cavity; the first valve is mounted below the crushing cavity. By adopting the crushing stirring machine for preparing the megestrol acetate suspension, megestrol acetate tablets can be uniformly crushed, and after being mixed with water and taken by a patient, the medicine of uniform granules is large in distribution area in a gastrointestinal tract, rapid to absorb, high in bioavailability, and in addition small in partial irritation to the gastrointestinal tract since suspension granules are uniformly dispersed.