The BBC said Tennant, 33, would replace Christopher Eccleston who announced he was quitting after one series as the Doctor.
Tennant, who will star alongside Billie Piper, will be the 10th Time Lord.
“I grew up loving Doctor Who and it has been a lifelong dream to get my very own Tardis,” he said on Saturday.
“Taking over from Chris is a very daunting prospect—he has done a fantastic job of reinventing the Doctor for a new generation and is a very tough act to follow.”
I’m still bummed that Eccleston only signed up for the one season as I’m enjoying his portrayal quite a bit. The second episode aired on CBC this past Tuesday and I thought it was pretty good. The new series isn’t entirely what I had hoped for, but it’s close enough that I’m happy it’s back and I look forward to seeing what Tennant does with the role.