Andrew Dickehage was bitten on his face and hands as he walked on a street in Longmont about 5 a.m., the Longmont Times-Call reported Wednesday.
Dickehage hit the largest of the animals with his flashlight, but the other coyotes continued the attack.
"They were continuously jumping on me one after the other after the other," he told the newspaper. "It was non-stop. It was so dark all I could see was the glimmer of their eyes."
He said the attack lasted about a minute and a half before the animals gave up the attack and left.
Colorado Parks and Wildlife spokeswoman Jennifer Churchill said the attack was "really aberrant behavior" for coyotes because they were not defending their young or a food source.
Churchill said wildlife officers have tracked down and killed two of the coyotes and are seeking the third.