The embodiment of the utility model discloses an oil exchange device. The oil exchange device comprises a contaminated-oil pipe, a new-oil pipe, and an oil inlet, a coarse filter element, a pumping injection machine and an oil outlet which are connected in sequence; the contaminated-oil pipe comprises a first contaminated-oil pipe and a second contaminated-oil pipe; the new-oil pipe comprises a first new-oil pipe and a second new-oil pipe; the pumping injection machine at least comprises an oil bump, a three-way valve, a contaminated-oil channel and a new-oil channel, wherein the first port of the oil pump is connected with the coarse filter element; the second port of the oil pump is communicated with the first port of the three-way valve; the second port of the three-way valve is communicated with the first port of the contaminated-oil channel; the third port of the three-way valve is communicated with the first port of the new-oil channel; and both the second port of the contaminated-oil channel and the second port of the new-oil channel are communicated with the oil outlet. Because contaminated oil and new oil enter different channels, oil product pollution can be reduced; and therefore, a series of problems caused by oil product pollution are solved.