Police said the officer was shot in the stomach and was saved from serious injury by his bulletproof body armor, The Detroit News reported.
Lt. Stephen Colegio said police responded to an emergency call early Wednesday from a resident who said a man was holding a gun to a roommate's head.
"As officers approached, a 52-year-old male, from the Downriver area, confronted officers with a semi-automatic and fired two rounds at officers," Colegio said.
Officers opened fire and struck the gunman.
"He was dead at the scene," Colegio said. "We're still conducting interviews about the incident. But it appears there was a dispute between the residents of the home and [a] 21-year-old female who was also from the Downriver area."
At least 30 casings were found across the lawn, officials said.
"There's no doubt that the vest saved our officer from a fatal injury," Colegio said, adding the officer did not sustain serious injury.