Based on analyzing the traditional process to manufacture fin heat sinks(FHS), the production of FHS by the planing process was proposed, the mechanism of the fins' curl was investigated and the fins' surface finish was analyzed. Through controlling chip curl based on the continuous strip chips, flat straight fins were processed.Compared with the traditional processes, this process makes full use of material and the processed FHS has better heat transfer capacity, higher heat transfer efficiency and more reliability. The tool geometrical parameters and processing performance affect the fins' curl. The optimum processing parameters are: a cutter edge inclination angle of 0°, a rake angle between 50° and 55°, and a planing depth from 0.2 mm to 0.3 mm. The planing speed has little effect on the fins' curl.