Carl Pistorius is charged with culpable homicide over the death of a woman motorcyclist in a traffic accident, his lawyer said.
The case has no relation to the charges against Oscar Pistorius over the shooting of Reeva Steenkamp.
The Paralympic star - who was released on bail on Friday - denies murder.
The charges against Carl Pistorius over an accident involving his car in which a woman on a motorcycle died date back to 2010 but have only just emerged, local media reports say.
They were confirmed to the BBC by Pistorius family lawyer Kenneth Oldwage.
The accident took place in the town of Vanderbijlpark, an hour's drive south of Johannesburg.
Police conducted tests on Carl Pistorius and he was found to have no alcohol in his blood at the time, the BBC's Milton Nkosi in Johannesburg says.
He is due in court at the end of March, which means his trial may end before his younger brother Oscar's is due to begin on 4 June.
Carl Pistorius was a constant presence at his brother's four-day bail hearing.
Oscar Pistorius admits shooting Reeva Steenkamp at his home on Valentine's Day but denies murder, saying he mistook her for an intruder.
- BBC
