Breaking: Treehouse illustrator Terry Denton dies aged 76 - ABC News & Headlines – Australian Broadcasting Corporation

Terry Denton has died at the age of 76. (Supplied: Facebook)

Children's author and illustrator Terry Denton has died at the age of 76, surrounded by his family in Victoria.

Denton had a creative partnership over three decades with author Andy Griffiths, illustrating the Treehouse books, including the 13-Storey Treehouse, which sold more than 10 million copes.

Griffiths said that he and his long-time collaborator had "a match made in heaven".

Australian children's author and illustrator Terry Denton, best known for his work on the popular Treehouse series, has died aged 76.

His literary agency Curtis Brown and publisher Pan Macmillan announced that Denton died surrounded by his family on Monday.

Denton enjoyed a creative partnership spanning three decades with author Andy Griffiths, illustrating the Treehouse books, beginning with the 13-Storey Treehouse, which sold more than 10 million copies worldwide.

He was also known for his Gasp! series, which was adapted for television.

No cause of death was revealed, but Denton had suffered poor health in recent years.

Griffiths paid tribute to his longtime collaborator, describing working and playing with Denton over three decades as "an honour and a pure delight".

"I'll miss him forever, but he's at peace now," Griffiths said.

"I'm incredibly grateful for his legacy, that we were able to get so much out to the children of Australia and the world."

Terry Denton (right) with his collaborator Andy Griffiths in 2018. (ABC News: Dave May)

Over the decades, Denton and Griffiths built global profiles as pranksters, the kind of larrikins that Australia is famous for.

"We were quite different in many ways. It's that difference that makes a creative partnership work … it was a match made in heaven," Griffiths said.

"He had a complete lack of ego. In the books, we were mad at each other all the time, but in real life, it was a very harmonious relationship.

"We would supercharge each other. I would create a structure and he'd come in and throw a spanner in the works.

"We would play with words, play with pictures, play with ideas."

Terry Denton had already worked on almost 30 books when he met Andy Griffiths in the 1990s. (ABC News: Dave May)

The 78-Storey Treehouse became the fastest-selling book in Australian history when it went on sale in 2016.

Although Griffiths lived only a 90-minute drive away from Denton in Victoria, he had not seen his co-collaborator for several years.

"As his health declined, he spent all his time with his family, and I totally respected that," he said.

"We always joked that we would go to 13 books with the Treehouse series, and after we finished number 13, the end came."

The Just series is still popular three decades after it first hit the shelves. (ABC News: Dave May)

Denton won several major awards across his career, including the Children's Book Council of Australia Picture Book of the Year Award in 1986 for Felix and Alexander.

The second youngest of five boys, Denton was born and grew up in Melbourne.

Denton is survived by his wife Kristen, his children Imogen, Eve and Max, and his grandchildren Georgia, Lucy, Charlie, Alfie and Felix.