The utility model relates to an oil filler plug for an axle. The oil filler plug for the axle comprises an oil plug, an O-shaped ring and a sealing ring, wherein the oil plug consists of a main body and a suspension screwing end part, the main body is provided with external screw threads, the O-shaped ring is sheathed outside the main body, the sealing ring is arranged between the inner side of the suspension screwing end part and the O-shaped ring, a placing groove of the O-shaped ring is formed between the sealing ring and the main body, and the sealing ring is a rubber ring. The sealing ring is added between the end part of the oil plug and the O-shaped ring, the sealing ring rotates along with the oil plug main body when the oil filler plug is tightly screwed, the O-shaped ring does not move, the sealing ring deforms through extrusion after the oil filler plug is tightly screwed, and the O-shaped ring cannot deform through extrusion, so the service life of the O-shaped ring is ensured, the replacement frequency of the O-shaped ring is reduced, and the use cost of the oil filler plug is reduced.