Sein Win (Burmese: စိန်ဝင်း, pronounced: [sèiɴ wɪ́ɴ]) is a former Chairman of National Coalition Government of the Union of Burma, a "government in exile". He was made unofficial Prime Minister of the Union of Burma, on being elected by the 1990 People's Assembly known as the National Coalition Government of the Union of Burma, a government-in-exile since 1990.