In order to study the response characteristics and failure mechanism of a super-large cooling tower under downburst specific wind，the highest cooling tower，i.e.，228 m high，of the world in construction in Northwest China is taken as the object. The multi-scale finite element model of the structure is established by using the layered shell element method. The internal and external fluctuating wind pressures of super-large cooling tower under three typical conditions of downburst are obtained based on the LES.The whole process of wind-induced collapse of super-large cooling tower is analyzed. Combined with IDA，the failure mechanism of the super-large cooling tower under downburst is refined. The collapse invalidation principle of the super-large cooling tower driven by downburst is established. The results show that the wind pressure distribution on the surface of the tower under downburst is significantly different from that under normal wind. The failure mechanism of the super-large cooling tower changes from concave mechanism to outward mechanism with the increase of downburst center distance. When the energy failure index K≥2，the super large cooling tower collapses.