The 33-year-old singer and the chart-topping rap star have teamed-up to record 'Rumors' together, and Lizzo relished the experience of working with her on the new single.
Asked what she loves about the rapper, Lizzo explained: "Cardi B is the ultimate. She, to me, has always done it right.
"Everything that she said, every way that she's reacted because you know why? It's because she was true to herself the whole time. She's a ground breaker. You can't deny her ability. She's a superstar.
"She has changed the game forever for a lot of us, a lot of women. I don't even think she realises she's doing it because it's just like, I'm trying to just be successful. I'm trying to get this money. I want to live a happy life. She just follows her heart. That's what I love about her."
Lizzo was determined to work with Cardi, 28, as soon as the possibility arose.
She told Zane Lowe on Apple Music 1: "There was no one else for it. There was literally no one else. From the day the ink dried on her Atlantic contract, I said, 'Please get me on a song with Cardi B.' She's just funny. I like funny people and she can rap. You know what I'm saying?"
Lizzo also feels that working with Cardi makes her more "cool".
Reflecting on her teenage years, she said: "I was a nerd. All the people back home in the SWAT and A Leaf who are going to see this music video, I'm in a music video with Cardi B. And I was walking through the hallways with sweaty hair, reading fantasy novels. A nerd, a geek, a band nerd. And I cried because I was like, what a full circle moment. I made it.
"I always wanted to be cool. You know what I'm saying?"