Police in Arlington, a city in the Dallas-Fort Worth metropolitan area, said the officer, who was still in training, responded early on Friday to a call about a burglary in progress.
Officer Brad Miller, 49, confronted a man who was suspected of driving a vehicle through the front of a car dealership, police said in a statement. Miller's race could not immediately be confirmed.
"There was an altercation during which at least one officer discharged his weapon," police said.
The Tarrant County Medical Examiner's Office identified the deceased suspect as Christian Taylor. The medical examiner did not list a manner or cause of death in online records.
Arlington police said Taylor was unarmed before he was killed. Miller was still in training after graduating from the police academy in March, authorities said.