A total of 4967 observations of 385 tropical cyclones (TCs) in the Northwest Pacific Ocean from 2001 to 2014 from the Best Track data, the Tropical Rainfall Measuring Mission (TRMM) satellite data and the National Centers for Environmental Prediction (NCEP) reanalysis data were classified to compare and analyze the response of environmental vertical wind shear and water vapor field on TC structural change. The results show that intensify TCs are mainly accompanied by east wind shear, and weaken TCs are mainly accompanied by west wind shear. Under the strong vertical wind shear (v > 5 m/s), there is no obvious water vapor anomaly on TC structural change. Under the weak vertical wind shear (v ≤ 5 m/s), the intensify (weaken) TC is accompanied by positive (negative) water vapor anomaly.