（口吃者）路易二世 （法语：Louis II le Bègue，846年11月1日－879年4月10日）是法兰克帝国皇帝（常等同于神圣罗马帝国皇帝）兼西法兰克王国国王（常等同于法国国王），查理二世（即秃头查理）和妻子奥尔良的厄门特鲁德的长子，是加洛林王朝的阿基坦国王（称路易三世，法语：Louis III，866年—879年）和西法兰克王国国王（称路易二世，877年—879年），但他并没有继承父亲的帝位、加冕为皇帝，导致自查理大帝以后由加洛林王朝君主垄断的所谓的“罗马人的皇帝”之位首次空缺。

Louis the Stammerer (French:Louis le Bègue) (1 November 846 – 10 April 879) was the King of Aquitaine and later King of West Francia. He was the eldest son of Charles the Bald and Ermentrude of Orléans. During the peace negotiations between his father and Erispoe of Brittany, Louis was betrothed to an unnamed daughter of Erispoe in 856. It is not known if this was the same daughter who later married Gurivant. The contract was broken in 857 upon Erispoe's murder.