The safety and reliability of power transmission lines are the cornerstone of the stable operation of the national economy. However, in recent years, with the frequent occurrence of extreme weather events and geological disasters, the damage suffered by transmission lines is increasing, which poses a serious challenge to the stable operation of the power system. In order to promote the progress and development of the theory of disaster-resistant design of transmission lines, this paper discusses in depth the disaster cases that have occurred, analyses in detail their causes and damage modes, and comprehensively evaluates the various methods and measures currently adopted to ensure the safe operation of transmission lines. Through the systematic summary and conclusion of these issues, it aims to uncover design flaws. Based on this, targeted suggestions are proposed to enhance transmission lines’ resistance to external loads.