Sanef said it received a report of verbal attacks and threats of physical harm to journalists from television station ANN7, which is owned by the controversial Gupta family, when they were covering a protest in Cape Town last week.
Sanef said the perpetrators were members of the public.
It said freedom of the media and freedom of expression were enshrined in the Constitution and should be respected by the whole society.
"Journalists should be allowed to conduct their work without fear or favour, we also wish to point out that in April 2016 we protested and met with the leaders of the Economic Freedom Fighters when they made threats to bar ANN7 journalists from their events as we believe that journalists are workers and should enjoy freedom of association," said Sanef.
The editor's forum also called on police to speedily deal with reports of intimidation of journalists to prevent them from doing their job.