The So Sick hitmaker was by his partner's side at a hospital in Atlanta, Georgia as baby Madilyn was born - and he admits his love for his new daughter is overwhelming.
He tells People.com, "I've been in love before but this feels like nothing I've ever felt. Like I'm in love for the first time."
And he's also taken to his Twitter.com page to reassure fans that Madilyn is doing well.
In a post on the site, Ne-Yo writes, "She's healthy and happy. Welcoming that lil' girl to the world last night defined for me what 'willing to kill and die for' truly means. My world, my life, all hers."