Officers responded to the scene, in the 1700 block of South Hanford Street, at 10:20 p.m. Thursday after receiving multiple reports of shots fired, said Detective Patrick Michaud of the Seattle police.
Officers arrived within a minute and found two men with serious gunshot wounds.
Medics took both of the injured men to Harborview Medical Center with life-threatening injuries. One of the men later died and the other is still in the hospital.
No one else was hurt.
Witnesses said they heard arguing just prior to gunshots being fired in an alley there. There was no immediate word on what led up to the fight.
Seattle homicide detectives are investigating the case. They said there is no reason to believe there are any additional suspects in the case.