Based on the observed data and simulated results, this paper studies the structure characteristics and cause of catastrophic wind caused by super typhoon Meranti(typhoon "1614"). It is the strongest typhoon affecting Xiamen since typhoon "5903", and its impact radius is relatively small. Before landing, the local strong wind in typhoon circulation is characterized by periodic fluctuation. The azimuth change of the local strong wind relative to the typhoon first turns clockwise, then turns counterclockwise with the typhoon approaching. Simulated strength of typhoon Meranti based on the wind-pressure relation is in good agreement with the observed result. After landing, typhoon Meranti is affected by terrain friction, which makes the wind speed on the left side of typhoon stronger than that on the right side. Numerical simulation analysis shows that the horizontal advection of wind vector and the pressure gradient term are the main physical factors causing the local catastrophic wind. The strong wind area of typhoon Meranti shows obvious meso-scale characteristics. Wind around the eye wall is strengthened by the vertical air transportation with higher momentum and the momentum downward propagation effect.