Nguyễn Phúc Thái (chữ Hán: 阮福溙, 1650–1691) was the ruler of Cochinchina from 1687 to 1691. During his short rule, a small rebellion by Ming Chinese was put down.

Nguyễn Phúc Thái was also known as Nguyễn Phước Trăn, courtesy name Ngạn (彥). He was the second son of lord Nguyễn Phúc Tần. Nguyễn Phúc Thái took the title Hoằng Quốc-công (弘國公 ; National Duke of Hoằng, different from Quận-công as Local Duke). With the end of the Trịnh–Nguyễn War, not much of note happened during Nguyễn Phúc Thái's rule. It is reported that he put down an uprising by Chinese immigrants who had settled in Saigon.

In 1689, he ordered an invasion of Cambodia. However, the Vietnamese general withdrew after meeting with the Cambodian king Chei Chettha III's envoy, a beautiful woman. In 1690 Nguyễn Phúc Thái sent a more famous general, Nguyễn Hữu Hào, who also retreated after meeting the same woman, waiting for presents that never came.^[1]

On February 7, 1691, Nguyễn Phúc Thái died and was succeeded by his eldest son, Nguyễn Phúc Chu.