The 20-year-old will line up as a stagiaire for the start of Tour of Utah in early August before joining the team on a multi-year contract next year.
Howson won bronze in the 2012 U23 Individual Time Trial World Championships and ORICA-GreenEDGE's sporting director Matt White is looking forward to tapping into the youngster's potential.
“Damien has shown strong progression within our national program,” White said. “We’ve seen obvious improvements from him first with Jayco-AIS last year and then this year with the Jayco-AIS World Tour Academy.
"He’s ready to turn professional, and we’re ready to support his development.”
Howson, the Australian U23 national time trial and Oceania TT champion, has already enjoyed some success in Europe.
He won the Trofeo Alcide Degasperi and came third overall at Thüringen-Rundfahrt this year.
“This is a dream come true,” said Howson. “Many riders dream of racing in Europe, turning professional, riding in the World Tour and eventually getting to do races the biggest races in the world like the Tour de France. After eight years of riding a bike, I’m on my way.
“Being an Aussie on an Aussie team should help me make the jump from my U23 team to the World Tour more easily,” he added. “I also think my style of riding suits the team, and the team’s approach to racing suits me. We should work well together.”
“I’ve steadily improved over the last few years I’ve been able to deliver some big results this year, which has been pleasing. I’ve learned a lot about racing with the national team, and I’ll learn even more racing with ORICA-GreenEDGE. I hope that I’m able to use my strengths and knowledge to help the team while they help me.”