By simulating the evolution of spin periods of magnetized neutron stars which interact with their environment in binary systems,we investigate the Galactic population of high mass X-ray binaries (HMXBs).The number of HMXBs in the Galaxy is between 190 and 240,and their birthrate is from 5.9 × 10-5 yr-1 to 6.3 ×10-5 yr-1.Comparing the Corbet diagram (the positions of the spin periods vs.the orbital periods of HMXBs ) in our model with the associated observations,we find that the stellar wind structure and the process of matter transfer are very important for understanding HMXBs.