The invention provides an automatic waste oil discharge device based on sealing rings. The device at least comprises an equipment end cap, a rotary shaft, a movable ring and a static ring. The movable ring is composed of an inner movable ring body, an outer movable ring body and a connection ring, the rotary shaft is axially sleeved with the inner movable ring body, the inner movable ring is sleeved with the outer movable ring, an axial flow guide stair is distributed on the outer circumference of the left end of the outer movable ring body, and a stirring stair is evenly distributed on the outer circumference of the right end of the outer movable ring body. The static ring is composed of an inner static ring body, an outer static ring body, a fixing ring and an isolation ring, the isolation ring is fixed to the inner circumference of the right end of the outer static ring body and located between the flow guide stair and the stirring stair, the inner static ring body is located between the inner movable ring body and the outer movable ring body, an axial through oil discharge channel is formed in the isolation ring and located above the axis of the rotary shaft, and an oil discharge hole is formed in the position, corresponding to the flow guide stair, at the bottom of the fixing ring. By means of the automatic waste oil discharge device, automatic oil discharge can be achieved, and meanwhile the holding volume of oil in a sealing cavity is guaranteed.