The invention discloses a portable oil inlet device. The portable oil inlet device comprises a detachable trolley, a primary filter tank, an oil pump, a micro filter tank, a primary filter net, an oil inlet pipe, a first conveying pipe, a second conveying pipe, an oil outlet pipe and a clamping mechanism, wherein the primary filter tank and the micro filter tank are fixedly arranged on the detachable trolley; the primary filter net is vertically, detachably and fixedly arranged in the primary filter tank and divides the primary filter tank into an oil inlet cavity and an oil outlet cavity; the oil inlet pipe, the oil inlet cavity, the oil outlet cavity, the first conveying pipe, the oil pump, the second conveying pipe, the micro filter tank and the oil outlet pipe are sequentially communicated; the micro filter tank comprises a tank body and a cover body; the clamping mechanism is used for clamping the cover body in an opening end of the tank body in a sealing way. The portable oil inlet device disclosed by the invention is convenient to move and is capable of removing impurities in oil.