Leakproof oil bearing box, the use of a joint type of oil ring to swing the high-speed rotating bearing oil to the inner wall of the bearing box flow back to the oil pool; In addition to convenient maintenance and preventing friction accidents, semi-open aluminum oil seal can be used to cut back some of the dilute oil along the shaft. The lateral pressure plate root blocks a small amount of dilute oil; The upper part of the bearing box is equipped with a ventilation plug to reduce the micro-positive pressure in the bearing box, ensuring no oil leakage and good dust protection performance.