介绍了架空送电线路设计规范对复合绝缘子串的设计安全系数的规定，比较了悬垂串和耐张串在覆冰条件、大风条件和年平均气温条件下的受力情况。通过几处典型气象区的气象数据对比，指出耐张串的运行条件比悬垂串恶劣，运行生命期的蠕变更为严重，在设计上应区别对待。最后给出了复合绝缘子耐张串安全系数取值的建议。

This paper introduced the specified value of composite insulator’s design safety factor in the design code for overhead transmission line, and compared the force condition of suspension string and tension string in different conditions, such as ice, strong wind and annual average temperature. According to the comparison of meteorological data in several typical areas, this paper pointed out that the design must be different between tension string and suspension string, due to the operational condition of tension string was worse than that of suspension string, and the creep in operation life period of tension string was more serious. Finally, the value of design safety factor was suggested for composite insulator tension string.