The utility model discloses an electric motor leakage-proof structure of a TCT (Thin prep Cytologic Test) machine. The electric motor leakage-proof structure is characterized in that a rotating shaft is of a ladder-shaped platform body structure, one end of the rotating shaft with larger diameter is connected with a sample liquid bottle seat, and one end of the rotating shaft with smaller diameter is connected with an electric motor rotating shaft; the inner side surface of a bearing seat is provided with a first platform body, a bearing is clamped between a ladder-shaped platform body of the rotating shaft and the first platform body at the inner side surface of the bearing seat, and the bearing is fixedly arranged in the bearing seat through a bearing base plate; the outer side surface of the bearing seat is provided with a second platform body, the second platform body is clamped on a shaft hole of a datum plate, and a vertical plate of the second platform body is higher than the datum plate; and an electric motor is connected with the datum plate through an electric motor installation plate. Compared with the prior art, the electric motor leakage-proof structure disclosed by the utility model has the advantages that the serious problems that the bearing and the rotating shaft are corroded as liquid splashing from the sample liquid bottle directly flows into the bearing seat when in high-speed rotation, thus the bearing and the rotating shaft are rusted, the rotating speed is slowed down, and even the bearing and the rotating shaft cannot work are effectively solved, and the service life of a machine is prolonged.