The invention relates to the technical field of lubricating oil processing accessory devices, and especially relates to a uniform-stirring lubricating oil blending device. The device improves the stirring efficiency and the stirring effect of lubricating oil, and improves the blending quality of the lubricating oil; and the internal of the working chamber of the device can be easily cleaned afterthe end of working to facilitate subsequent use, so the use reliability is improved. The device comprises a mixing tank, and the working chamber is arranged in the mixing tank; and the device also comprises a pedestal, a left support plate, a right support plate, a tube body, a servo motor, left ball bearings, right ball bearings, a plurality of square tubes, a plurality of stirring rods, a bafflecover, a driving gear, toothed ring and a plurality of baffle plates, the outer side of the toothed ring is provided with a toothed structure, the device further includes a cleaning box and a flushing pump, the front ends and the rear ends of the square tubes are provided with a plurality of flushing holes in a communicating manner, a sealing groove is arranged at the outer side of every flushinghole, a diaphragm is arranged in every sealing groove, one end of every diaphragm is hinged to the corresponding sealing groove through a torsion spring, and a dirt discharging tube is arranged at the bottom end of the mixing tank.