Hartley raced in Formula Three in 2008
Brendon Hartley has been granted his motor racing super-licence and will join Red Bull as a reserve driver.
The New Zealander, 19, said: "I must thank Red Bull for all their support and this is another step on the path to reaching my goal of being an F1 driver.
"I know that with the new in-season testing ban, I'm not likely to get much cockpit time, but I will be part of the team and will learn a lot from that."
Hartley tested for Red Bull in December but needed his super-licence to race.
David Coulthard, who retired at the end of last season, was retained as a stand-in reserve driver while Hartley waited for his licence.
Red Bull's regular drivers are Germany's Sebastien Vettel and Australian Mark Webber.
Vettel won the team's first grand prix in Shanghai last month and they are currently second in the constructors' standings behind Brawn GP.