Samora Mangesi tweeted photos of the injuries he sustained in the alleged assault, which he said happened on Friday.
He and his two female friends were called "monkeys", he said.
When they asked why they were being insulted, he was beaten unconscious.
The attack was right after he and two female friends stopped to help a group of white people whose car had overturned.
The alleged assault took place in the city of Johannesburg, South Africa.
Mangesi, who is a presenter for SABC, said he received injuries to his face and was bruised along the side of his body after being kicked on the ground.
"Even whilst I was being put in the ambulance, one of these guys tried to run my friend over with his bakkie [pick-up truck] and the paramedics had to intervene."
Talks of the assault has sparked anger on social media and calls for a police investigation.