The 36-year-old actor is best known for his role in "The Hangover."
Cooper said he considers himself just "decent looking" but says his first thought was how happy his mother would be to hear about his new title.
He is grabbing the spotlight from last year's winner, actor Ryan Reynolds.
But Cooper has a ways to go before being in the elite circle with Brad Pitt and George Clooney, who have each received the title multiple times.
