Tuan can refer to:
- Tuan Do, the founder of technology blog, TechWalls
- Brush-tailed phascogale, an Australian marsupial animal
- Zaiyi, Prince Duan (or Prince Tuan), a Qing Dynasty prince and statesman
- Duan Qirui (段祺瑞) (Wade-Giles Tuan Ch'i-jui), a powerful Chinese warlord in the early 20th century
- Tuan mac Cairill, a figure in Irish mythology
- an Irish music band formed by Brendan McFarlane
- Mr./sir/lord in Malay or Indonesian language, as in the fictional "Jungle Jim" radio stories whereupon Jim's friend, Kolu addressed him as "Tuan Jim"