Mandahai (Manchu: ᠮᠠᠨᡩᠠᡥᠠᡳ, Chinese: 滿達海; 30 April 1622 – 15 March 1652), was an imperial prince of the Qing dynasty and one of Nurhaci's grandson.
Mandahai was born in the Aisin Gioro clan on 30 April 1622 as the seventh son of Daišan.
His mother was Daišan's princess consort Lady Yehe Nara, who also bore the eighth son, Hūse.
In the next year, he joined his uncle, Ajige, in pursuit of the rebel leader Li Zicheng.
After his death, Mandahai was accused of confiscating a part of Dorgon's property and was posthumously demoted.