The Guangzhou New TV Tower with a total height of 610 m is the tallest tower in the word. It comprises a 454 m high main tower and a 156 m high antenna mast. The main tower is a tube-in-tube structure consisting of a steel lattice outer structure and a reinforced concrete inner structure. The antenna mast is a steel structure founded on the tope of the main tower. To ensure the safety during construction of this challenging structure, the failure probability estimates under wind load during construction has been performed. The estimates consists of three steps. First, the cumulative distribution functions (CDFs) of static wing loads per year at Guangzhou site are given out. Secondly, the CDFs of horizontal displacement responses during construction of the Guangzhou New TV Tower to static wind loads are derived based on static analyses of a reduced finite element (FE) model of the structure. Finally, anti-wind safeties during construction of the structure are estimated based on the structural reliability method. The study not only provides useful data concerning the structural safety of the Guangzhou New TV Tower during construction but also is of considerable referential importance in estimating the safety of an in-construction supertall structure.