Netwerk24 reported that the 76-year-old died of a heart attack in the early hours of Monday morning.
The news comes shortly after it was announced that Afrikaans singer, Randall Wicomb, died on Sunday morning after a long battle with prostate cancer.
Barnard leaves behind his wife, Katinka Heyns, and his sons Simon, Johan, Stephan, Tian and Reghard.
Barnard is best known for his award-winning writing which included works like Boendoe, Mahala and the radio drama Die Rebellie van Lafras Verwey.
Afrikaans literature has lost some of its giants this year with the deaths of André P. Brink, Ena Murray and T.T. Cloete.