A spot-test of cooling after the finish-rolling was performed for the typical H-beam and the temperature field during the process and residual stress in the beams after the cooling were measured. By using finite element method, the cooling temperature-field of the H700×300 H-beam was simulated and the thermal stress distribution formed in this process was calculated by using thermo-mechanical coupling function. The simulation results matched well with the data obtained on the spot. The accurate description performed in this paper for the temperature field and residual stress distribution of H-beam during cooling process is especially helpful to the manufacture plant. According to the results the reasonable technical parameters can be constituted to control the temperature of the beam in the cooling process and reduce the residual stress in the final product.