The invention discloses a limiting-device-provided oil rail oil atomizer on a car. The oil rail oil atomizer comprises an oil rail body, an oil atomizer body and an oil atomizer base; the oil atomizer body and the oil rail body are installed together through the oil atomizer base, the oil atomizer body is provided with a limiting ring and a first limiting device, a second limiting device is arranged on the oil atomizer base, and a protruding edge is arranged on the periphery of the limiting ring; the first limiting device comprises a fixing ring and a first connecting rod, the fixing ring is connected to the connecting end of the oil atomizer body in a sleeving manner, and one end of the first connecting rod is fixedly installed on the fixing ring; and the second limiting device comprises a stopping ring and a second connecting rod, one end of the second connecting rod is fixedly installed on the stopping ring, the first connecting rod and the second connecting rod are each provided with a rubber washer, the first connecting rod penetrates the protruding edge to be installed in a second penetration hole of the stopping ring, and the second connecting rod penetrates the protruding edge to be installed in a first penetration hole of the fixing ring. Relative movement of the oil atomizer body and the oil atomizer base can be effectively limited, and the oil atomizing effect is not influenced.