The Black Eyed Peas star praised the Canadian teen sensation's talent and insisted that the general public don't realise his ability as an artist.
"[He is] very talented, beyond what people probably think he's capable of. I've worked with him and [seen] how talented he is," will.i.am told Access Hollywood.
"In the industry, especially as it's changing, you're going to [need] some type of real talent. Maybe people can't see [it] right now, but 10, 15 years from now, he'll still be around."
will.i.am has worked with Bieber on a track for his forthcoming solo project #willpower, which is due out later this year.
Meanwhile, Bieber recently confirmed that 'All Around the World' will be the second single to be lifted from his recent album Believe.
Listen to Justin Bieber's 'All Around the World' below: