Nimri's mother is Navarrese and her father is Jordanian; his name is Karam Nimri. She has a brother named Karim Nimri, a half-brother named Andre Nimri and two half-sisters named Sara and Nadia Nimri. Najwa also has a cousin who is a singer named (Antix) Alexander Nimier. When she was a child she moved to Bilbao and now lives in Madrid.
Her first important film role was in Salto al vacío, the first movie by film director Daniel Calparsoro. Her career as a singer started with small groups. In 1996, she formed the band Najwajean with Carlos Jean. She has also released three solo albums. She was married to Daniel Calparsoro and in 2004, she had a son, Teo.