| Honorific Prefix: | Doctor |
| Nguyễn Lưu Viên | |
| Office: | Deputy Prime Minister of South Vietnam |
| Term Start: | 1 September 1969 |
| Term End: | 4 April 1975 |
| Alongside: | Phan Quang Đán (1974–1975) |
| Primeminister: | Trần Thiện Khiêm |
| Predecessor: | Trần Thiện Khiêm |
| Term Start2: | 13 July 1966 |
| Term End2: | 28 October 1967 |
| Alongside2: | Nguyễn Hữu Có |
| Primeminister2: | Nguyễn Cao Kỳ |
| Successor2: | Phạm Đăng Lâm |
| Term Start3: | 4 November 1964 |
| Term End3: | 16 February 1965 |
| Alongside3: | Nguyễn Xuân Oánh |
| Office4: | Minister of Internal Affairs of South Vietnam |
| Term Start4: | 4 September 1964 |
| Term End4: | 14 February 1965 |
| Predecessor4: | Lâm Văn Phát |
| Successor4: | Nguyễn Hòa Hiệp |
| Birth Date: | 21 November 1919 |
| Birth Place: | Trà Vinh province, Cochinchina, French Indochina |
| Death Place: | Springfield, Virginia, U.S. |
| Party: | National Social Democratic Front |
| Otherparty: | Bloc for Liberty and Progress (1960–1963) |
| Spouse: | Nguyễn Thị Trinh |
| Children: | 3 sons |
| Relatives: | Nguyễn Khánh (nephew) |
| Alma Mater: | Hanoi Medical University (M.D.) |
Nguyễn Lưu Viên (21November 1919[1] 18September 2017) was a South Vietnamese doctor and politician who served as Deputy Prime Minister of South Vietnam under various prime ministers. He also served as Minister of Internal Affairs of South Vietnam under Prime Ministers Nguyễn Khánh and Trần Văn Hương.
He was born on 21 November 1919 to a wealthy family in Trà Vinh province. He earned his M.D. at the Hanoi Medical University[2] and worked as a doctor prior to entering politics.[3]
As South Vietnam was on the verge of collapsing to the advancing forces of North Vietnam Viên left for Guam on 29 April, a day before the government of General Dương Văn Minh announced South Vietnam's surrender on 30 April 1975 to the Communist regime.[4] After arriving in Guam, Viên was then relocated to Camp Pendleton along with other Vietnamese refugees.[5] [6] Afterward, Viên decided to further his studies in Oklahoma before deciding to relocate to Union City, Tennessee where he worked as a doctor at Baptist Memorial Hospital for 11 years.[7] [8] In 1988, he retired and then relocated to Virginia where he would live out the remainder of his life.
He died at his home at the age of 97 in Springfield, Virginia on 18 September 2017.[9]