Gregory McMichael, aged 64, and Travis McMichael, aged 34, were detained on Thursday by the state bureau of investigation.
They were both charged with murder and aggravated assault, investigators said in a statement.
Mr Arbery, 25, was jogging in February when he was confronted by the pair.
The failure to bring charges against the McMichaels, who are white, in the weeks after the shooting provoked widespread outrage.
The Georgia Bureau of Investigation announced late on Thursday that both men had been taken into custody.
The bureau said the father and son had confronted Mr Arbery with two firearms, and it was the younger McMichael who shot and killed him.
I've seen somewhere the possibility of a third suspect. Story is developing.
Edit: I misread. They are looking for the individual who sat on the evidence in the murder and released the tape later.
Ahmaud Arbery: Father and son charged with murder of US black jogger
Ahmaud Arbery was on a residential street in February when he was confronted by the pair.
www.bbc.com