In view of the collapse accidents of most high-attached tower cranes under typhoons, this paper makes an in-depth analysis on the strength of tower cranes under typhoons and discusses the maximum attached height of attached tower cranes under typhoons. First, based on the average wind speed profile of typhoon exponential law, the exact calculation formula of the maximum bending moment of the tower crane under ideal conditions and the practical calculation formula under different loads are derived. Secondly, the overhang section of the attached tower crane is equivalent to the elastic support model, and the exact calculation formula of the maximum bending moment subjected to this model and the practical calculation formula under different loads are derived. Finally, the principle of strength equality is proposed, stating that the maximum bending moment of the ideal tower crane equals that of the attached overhang tower crane. This allows us to establish the relationship between the maximum height of the overhang section and the maximum independent working height of the tower crane. The maximum height coefficient of the overhang section is further compared to evaluate the strength and stability of the overhang section in the typhoon state more comprehensively. In general, assuming the axial force is 0, the overhang height ratio under a typhoon can be checked according to the overall stability formula. In the case of different coaxial force coefficients, the ratio of overhead height will be different.