Barr’s apology to Mr Soros, 87, comes just two days after he spoke to the Washington Post, describing her comments as “a total fabrication”.
Following Ms Barr’s initial tweet, Mr Soros's son, Alexander, wrote a piece in the New York Daily News criticising the comedian.
He wrote her tweet was “odious,” adding that his father, who was 13 when he was taken in by a Hungarian official, “did not collaborate with the Nazis”.
He added: “Roseanne Barr’s claims are not just an insult to my father, but [to] all those who endured the Holocaust”.
Mr Soros, one of the world’s most successful investors, was 14 when the Nazis occupied his native Hungary.
During this period, he hid that he was Jewish to escape Nazi persecution.
Ms Barr's attack on Mr Soros came as she made racist comments about former Obama aide Valerie Jarrett, which led to the popular revival of her sitcom Roseanne being cancelled.
