The cooling intensity of laminar cooling determines the microstructure of metal materials, thus affecting the performance of the product, while the heat transfer coefficient directly affects the cooling intensity. In this work, a method for obtaining the heat transfer coefficient of laminar cooling is presented. Through the process analysis, the distribution form of the heat transfer coefficient was a piecewise function which was composed of half wave sine and straight line with the nozzle as the center. The characteristic parameters of the piecewise function can be achieved by some calculations, which involved the structural parameters, operational parameters and experimental data. The experimental bench verified the accuracy of this method. The calculation results showed that when the amplitude is increased by 1 W/(m2?K), the relative decline of the metal material surface temperature reached maximum in the final area, which was -0.36 m2?K2/W, and the maximum relative change of section temperature difference was 0.07 m2?K2/W. When the period decreased by 1 s, the relative increment of surface temperature of metal materials reached the maximum value of 13.24 K/s in the last region, and the section temperature difference showed periodic changes with a range of -2.5~0 K/s.