It is a kind of refrigeration which has a trapezoidal frame corrugation fin oil cooler. It contains oil-in chamber, corrugation fin, oil-in pipe, short seal, long seal, intermediate bay, sawtooth turbulence, basal bay, oil-in pipe and oil-out chamber. Among them, the corrugation fin has trapezoidal frame, which can form a rectangle with its tangent plane in vertical direction in the air. In the air split, fin corrugation is a trapezoidal frame periodically. The ratio between the lower bottom of echelon form and the upper bottom is 4.5-5.5. The height of the echelon form is 1.5mm. This invention improves the power of the heater exchanger and decreases weight and size under the less resistance pressure.