The Hollywood hearthrob also revealed he is currently single and is not the "player" he is made out to be.
Bradley - who was previously in a long-term relationship with Renee Zellweger - said: "I'm a single 36-year-old male ... If you're a single man and you happen to be in this business you're deemed a player. But I don't see myself as a ladies' man."
Other famous hunks to make the top 12 of People's poll include Liam Hemsworth - who is dating Miley Cyrus - The Wire star Idris Elba, actor Chris Evans, Jennifer Aniston's man Justin Theroux and Ryan Gosling.
Bradley took the title from last year's winner Ryan Reynolds, who did not make the top 12 this year.
People magazine will publish its full list of the 100 Sexiest Men Alive in their next issue which hits newsstands on Friday.
People's top 12:
1. Bradley Cooper
2. Liam Hemsworth
3. Idris Elba
4. Justin Theroux
5. Chris Evans
6. Tim McGraw
7. Josh Charles
8. Joel McHale
9. Jason Momoa
10. Ryan Gosling
11. Alec Baldwin
12. Dylan McDermott
- BANG! Showbiz
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