Oil pump and diesel engine with oil pump

The utility model discloses an oil pump and a diesel engine with the oil pump. The oil pump comprises a pump body, a pump cover which is covered on and combined with the pump body, and a transmission assembly contained in the pump body. The pump cover is provided with an oil inlet and an oil outlet, and an oil way is formed between the oil inlet and the oil outlet. The transmission assembly comprises a driving shaft, an internal rotor fixedly sleeved on the driving shaft, and an external rotor sleeved on the internal rotor. The thickness of the internal rotor is even, and the thickness of the external rotor is uneven. The oil inlet and the oil outlet are arranged on two opposite sides of the driving shaft. The oil way through which the oil inlet can lead to the oil outlet is arranged between the internal rotor and the external rotor. The oil pump has the advantages that when volume increases, flowing volume and pressure increase at work time, sufficient lubrication of each part of the diesel engine can be guaranteed when the diesel engine is in normal operation, abrasion on each part of the diesel engine can be reduced, and service life of the diesel engine can be prolonged.