The couple and several others were hiking in the park in Montana over the weekend when the 125-pound bear cub charged them.
Hanna grabbed his pepper spray and sprayed the bear twice, but the wind misdirected it.
"He's about 10 feet right in front of me, I had the pepper spray right in his face," Hanna said. "I just unload the whole thing in his face right, and it went backwards because the pepper spray burns, and he went backwards and then he took off."
Hanna recently filmed a public service announcement encouraging hikers to carry pepper spray. He says this is the first time he has ever had to use it on a hike.