Why does Doctor Who have two hearts?

Oddly enough, Chritopher Eccleston, who played the tenth Doctor has commented on this issue. According to The Greatest Show in the Galaxy: The Discerning Fan's Guide to Doctor Who, "In early interviews upon first landing the role of the Doctor, Christopher Eccleston remarked that since the Doctor had two hearts, he risked the chance of having them broken twice as hard. While Eccleston never had the chance to demonstrate the full effects of a twice-destroyed Time Lord heart since he only served one brief but memorable season in the role, it would be David Tennant who had the honor of showing us the full emotional gravitas of the Doctor鈥檚 grief when the tenth Doctor shed two long-trailing tears at end of the story which may someday be referred to as 'the one with Cybermen and Daleks.'"

Sorry I didn't get the chance to answer this question, as I know the answer according to Dr Who canon. The reason is explained a number of times in the classic series, especially during the 3rd Dr era. Not enough room to explain here, but it can be found in wikipedia's entry on the series. Report It

One for the patience and one for himself. :)

so he can give twice the looooovvee to all the ladies

Dr who has two hearts? : )

Because he is NOT human.

He is from Gallifrey.

I'm sorry that the others are giving you silly answers but i cant explane to you why The Doctor has two hearts nether but i think Spacephantom will explane to you shortly.

He's from Gallifrey. The anatomy of people from their planet is different. It's the same reason Vulcans have an extra eyelid, and their heart is where you'd find the human liver.

Because he is an alien.