Robert Irwin has broken down in tears as he paid tribute to his mother Terri and late father Steve on the US version of Dancing With The Stars.

The wildlife conservationist performed a routine set to Phil Collins' You'll Be In My Heart.

"She's an absolute hero to me, because I was two when I lost Dad," he said during his intro package.

"As I got older, I started to realise just how hard it would have been for her to be there for us, and all the while continue Dad's legacy that her and Dad built together."

Irwin started to cry, insisting he had "never been able to capture the feeling of gratitude I feel for it".

"At every milestone, when I just wished that my dad was there, she was there. And that was enough," he said.

Irwin told viewers and the audience that his dance was for his mother, as well as "all the mums out there who don't get the recognition they deserve".

"This is for the single parents who work so hard every day to put one foot in front of the other," he said.

"If you can, go call your mum and tell her that you love her."