In a recent survey, more than one in three South African men admitted to rape.
The finding is the latest evidence in the country of a violent culture of patriarchy, reports the Guardian.
In the survey, more than three in four men said they had perpetrated violence against women.
Nearly nine in 10 men believe that a woman should obey her husband - and almost six in 10 women also agreed with the statement.
South Africa has one of the highest rates of rape in the world. Last year a survey by the Medical Research Council (MRC) found that 28% of men in Eastern Cape and KwaZulu-Natal provinces said they had raped a woman or girl.
A new MRC study in Gauteng, the country's wealthiest province, found that 37.4% of men admitted having committed a rape, while 25.3% of women said they had been raped.
The survey questioned 511 women and 487 men, of whom 90% were black and 10% white.
"We see a situation where the use of violence is so widespread that not only is it seen as being legitimate but I think quite often women forget it. They just see it as a normal effect," Rachel Jewkes of the MRC said.
Some 53.9% of men and 29.8% of women agreed that "a man should have the final say in all family matters", while 37.3% of men and 23.2% of women supported the view that "a woman needs her husband's permission to do paid work".
Asked about sexual entitlement in marriage, only 55% of both men and women said they thought "it is possible for a woman to be raped by her husband".
Some 38.7% of men and 29.3% of women thought that "a woman cannot refuse to have sex with her husband" and 22.3% of men and 8.8% of women felt that "if a wife does something wrong, her husband has the right to punish her".
The survey also found that 32% of men and women agreed that "in any rape case, one would have to question whether the victim is promiscuous", while 20.1% of men and 15.6% of women said that "in some rape cases, women want it to happen".
"What we see here is a set of attitudes reflecting men's views that they are legitimate in the use of violence against women, and women in many respects acquiescing to this," Jewkes said.
