Tie Guan Yin (simplified Chinese: traditional Chinese: pinyin: tiěguānyīn; Min Nan POJ: Thih-koan-im; Cantonese Jyutping: tit8 gwun1 yam1; literally meaning iron guanyin) is a premium variety of Chinese oolong tea associated with Anxi in the Fujian province. Named after the bodhisattva Avalokitesvara (best known as Guan Yin), it has also been translated as "Iron Goddess of Mercy" after the old translation for Guan Yin's name. Recently the tea has been grown in Nantou, Taiwan where it thrives.

Other spellings and names include Ti Kuan Yin, Tit Kwun Yum, Ti Kwan Yin, Tie Guan Yin, Iron Buddha, Iron Goddess of Mercy, and Tea of the Iron Bodhisattva, which is probably the closest English translation.