Police have confirmed one woman has been killed and another has been injured.
One woman in her 20s was shot in the leg and another forty-year-old was shot multiple times in the chest.
The woman shot in the chest has died.
Both people shot were not students at the school.
The shooting took place in a car park outside the school.
Police also say the shooting happened because of an argument.
A pregnant woman is also said to have been trampled on as the crowd fled.
Clayton County police are on the scene and investigating.
Video of the scene show around 15 police cars attending.
There were also search helicopters flying overhead.
Initial reports suggest the shooting took place during a graduation ceremony.
It comes less than 24 hours after a shooting in Santa Fe high school in Texas which left at least 10 dead.
A law enforcement official said 10 people were killed in the shooting; nine students and one teacher.
At least 12 people were hospitalised in the shooting.
The alleged gunman in the Texas shooting, named by police as 17-year-old Dimitrios Pagourtzis, was taken alive and is being held on charges of capital murder.
He is said to be a student at Santa Fe High School.