The invention relates to an automobile oil delivery pump, in particular to a diesel oil delivery pump assembly for a gradient self-adaptation system. The oil delivery pump assembly comprises a flange,a shell and an oil delivery pump body. The oil delivery pump assembly is arranged in a fuel oil tank and located at the opposite end of an oil sucking pipe of the fuel oil tank, it can be guaranteedthat the position near the oil sucking pipe is always filled with fuel oil, and normal fuel oil supply of an engine is guaranteed. The oil delivery pump assembly is fixed to the fuel oil tank throughthe flange, the shell of the oil delivery pump assembly abuts against the interior of the bottom of the fuel oil tank, the bottom of the flange and the shell are connected through elastic connecting pipe columns, it can be guaranteed that the oil delivery pump assembly is firmly mounted in the fuel oil tank and does not shake at will along with operation of a vehicle, and under the condition thatthe plane rigidity of the metal fuel oil tank is poor, and the bottom of the metal fuel oil tank is uneven, the elastic connecting pipe columns can also compensate for the bottom unevenness of the fuel oil tank.