The $3 million, 30-bed facility will open in the southern city of Davao in mid-2013, the US-based charity CURE said in a statement on its website where a video message from the Denver Broncos quarterback was also posted.
"I've always had a a special place in my heart for the country in which I was born and I'm very excited about this project," Tebow said in the message as he appealed for the public to join him in donating to the hospital's fund.
"This hospital will change the lives of thousands of children in the Philippines."
The Tebow CURE Hospital will specialise in bone disease and injuries for children, with about of a third of the young patients expected to be charity cases.
The hospital will house a "Timmy?s Playroom" to be used by children who undergo surgery.
The Tim Tebow Foundation, established in 2010, plans to build playrooms in children's hospitals around the world, and the Davao one will be the first.
CURE spokesman Matt Shandera told AFP on Friday that preparatory work was under way to build the hospital this year.
"We have people working on this project there," he said in a telephone interview from the United States.
Tebow, a devout Christian dubbed by some in the press as "God's quarterback", is known for late-game heroics leading to seemingly miraculous, come-from-behind victories for the Broncos in the National Football League.
Tebow was born in 1987 in Manila, the Philippine capital, where his Baptist parents were then serving as missionaries.
CURE, based in Philadelphia, is a faith-based charity that runs hospitals in health programmes in 20 countries for patients who are unable to afford medical care.