Duke Wu of Jin (simplified Chinese: 晋武公; traditional Chinese: 晉武公; pinyin: Jìn Wǔ Gōng, died 677 BC), ancestral name Ji (姬), given name Cheng (稱) and also known as Duke Wu of Quwo (Chinese: 曲沃武公; pinyin: Qūwò Wǔ Gōng), was the eighteenth ruler of the state of Jin.