Dempsey, 57, said he was "completely shocked" when he heard the news and thought it was a joke, noting "I've always been the bridesmaid."
"It's nice to have the recognition, and certainly my ego takes a little bump, but it gives me the platform to use it for something positive," Dempsey told People for the cover story.
Dempsey has grown in popularity over the years, starring in nearly 250 episodes of Grey's Anatomy as heartthrob neurosurgeon Derek "McDreamy" Shepherd to being a modern day prince charming in the 2007 musical film Enchanted.
Dempsey, married to makeup artist and beauty line founder Jillian, is most interested in how his children, Talula, 21, and 16-year-old twins Sullivan and Darby, will react to his new status.
"They're just going to make fun of me and pick on me and figure out every reason why I shouldn't be," he said.Â
"Which is good, they keep me young."
In December, Dempsey will be seen in the biopic Ferrari, directed by Michael Mann, portraying Italian Formula One driver Piero Taruffi opposite Adam Driver and Penelope Cruz.
When Dempsey found out the movie was being made, he took a risk and called Mann to ask for a part.
"I'd been following the movie for years, so I called Michael," he recalled. "That taught me if you really want something, you have to do it yourself."
Another passion project of Dempsey's includes the Dempsey Center, which he founded in honour of his late mother to support cancer patients and their loved ones.
8°C