（长者）克洛泰尔一世（法语：Clotaire I le Vieux，拉丁语：Chlotarius I，德语：Chlothar I.，意大利语：Clotario I；497年11月29日－561年11月29日）是法兰克王国墨洛温王朝的开创者克洛维一世的幼子，原为苏瓦松国王（511年起在位），后来先后吞并三位亡兄的奥尔良王国、兰斯王国和巴黎王国的领土，又吞并整个勃艮第王国，成为第二位统一的法兰克王国的国王（558年12月23日—561年11月29日在位），但他去世之后统一的王国被他的儿子们再次瓜分。

Chlothar I (c. 497 – 29 November 561), called the Old (le Vieux), King of the Franks, was one of the four sons of Clovis I of the Merovingian dynasty.

Although his father had united Francia for the first time, he had divided the kingdom between his four sons, and at the age of about 14 Chlothar inherited two large territories on the Western coasts, separated by the lands of his brother's Kingdom of Paris. He spent most of his life in an unedifying struggle to expand his territories at the expense of his relatives and neighbouring realms in all directions. Outright war with his brothers was avoided; they cooperated in attacking neighbouring lands in concert or swooping on lands when the ruler died. In both cases the spoils were then shared out between the participating brothers. By the end of his life he had managed to reunite the Frankish kingdom by outliving his brothers and grabbing their territories after their deaths. On his death Francia was once again divided between his four surviving sons; another had rebelled and been killed with his family.