Abstract: In this paper, the characteristics of coastal wind field in Zhejiang and its formation associated with typhoon Tapah (1917) are investigated in order to provide prediction clues using the data from conventional radiosonde and automatic station, the reanalysis data from NCEP/NCAR 1°×1° and 0.25°×0.25° and the data from TBB. Results show that strong winds had the characteristics of early influence, long duration, wide scope and strong intensity. The accumulation of pressure gradient between the typhoon circulation and the weak cold air along the coast of Zhejiang Province and the further increase of pressure gradient after development of typhoon circulation were one of the reasons for the early appearance of the typhoon wind. Vertical circulation was conducive to horizontal transmission and the downward transport of highlevel momentum, which leaded to a large range and strong intensity of wind. Dry cold air played a very important role in the process of strong winds. As the distance between the periphe-ral circulation of typhoon and the cold air getting closer, part of the dry cold air invaded the typhoon circulation. As the θ_se contour lines between the cold and warm air masses getting denser, the wind speed near the circulation increased. When the cold air continued to invade, the cold and warm air interaction accumulated and baroclinic energy released. At the same time, the warm structure in the lower layer of typhoon was occupied by cold air and the warm structure in the upper layer elevated, thus the formation of the upper warm and lower cold central structure leaded the denaturation and weakening of typhoon. The convergence and friction of the terrain also affected the redistribution of the wind field.