Investigators interviewed several people on the scene and at the hospitals. They say the shooting occurred after a gambling feud.
The victims' ages ranged between 13 and 21, a sheriff's office spokesman said.
The shooting happened just after 7 in the 4300 block of Sun Ridge Drive outside the Memphis city limits.
The sheriff's office said one person was dead on the scene and another was pronounced dead at a hospital. Three were being treated at Regional One and one at Le Bonheur.
The conditions of the four hospitalized victims ranged from serious to critical. The victims who were killed have not been identified.
Lt. Anthony Buckner said one of the victims called the sheriff's department to report he'd been shot. Five victims showed up at Methodist Hospital in Memphis.
Investigators believe that this was an isolated incident and that the victims knew the suspects.
No suspects are in custody. The sheriff's office asks anyone with information to call Crime Stoppers at 528-CASH.