Large demonstrations under the “Black Monday” banner were held in Cape Town, Johannesburg and the capital Pretoria.
Marchers dressed in black to commemorate the victims of hundreds of deadly “farm attacks” in recent years.
The protest actions halted traffic on main roads and forced police to divert vehicles on several major routes.
Monday’s day of action was coordinated by AfriForum, a campaign group that advocates for its largely white membership, many of whom speak Afrikaans.
It lobbies on issues including farm murders, hate speech and language rights, and is often critical of the African National Congress party, which has ruled South Africa for over two decades.
The group said in a statement that there have been 72 farm murders this year.
Its figures are disputed by officials in South Africa, where 52 people are murdered on average every day.
Monday’s protests came as news emerged that a 73-year-old farmer Bokkie Potgieter had been hacked to death at his home in Vryheid, a rural town in the eastern KwaZulu-Natal region.
Tensions are running high in South Africa after two white farmers convicted of forcing a black labourer into a coffin and threatening to kill him after they accused him of stealing from their farm were jailed.
A moment of silence for the victims of farm murders was held on Monday at the Voortrekker monument in Pretoria that celebrates Afrikaner identity and history.
“The government needs to recognise this isn’t ordinary crime,” AfriForum chief executive Karrie Kriel told AFP.
“They need to make a special plan like they do with rhino poaching or violence against women. There’s a lack of political will. The police minister was today more focussed on trying to discredit the march,” he said.
Police minister Fikile Mbalula tweeted an excerpt of an interview in which he said that while “farmers are strategically important” the issue had been “racialised and politicised”.
At one protest outside Johannesburg a truck ploughed into a group of praying farmers, apparently by accident.
Three people were injured in the incident which caused a multi-vehicle pile-up, local media reported.