Jens David Breivik, a former diplomat who lives in retirement in the south of France, said he first learned of his son's attacks from media websites.
"I couldn't believe my eyes. It was totally paralyzing and I couldn't really understand it," he said.
Breivik's parents divorced in 1980, and his father lived in London while he and his mother lived in Oslo.
In an interview with the Swedish tabloid Expressen, Breivik said he and his son have had virtually no contact with one another since 1995 (when Anders was 16), except for a "bland" phone call about 10 years ago.
"I don't feel like his father," said Breivik from his secluded home in southern France. "How could he just stand there and kill so many innocent people and just seem to think that what he did was OK? He should have taken his own life, too. That's what he should have done."
"I will have to live with this shame for the rest of my life. People will always link me with him," he said.
When asked what he would say to his son if he had the opportunity, Jens Breivik said he didn't know, and didn't know if Anders would listen. "He must live in another world; I do not think he would understand."
He added that his son should consider the sorrow and suffering he has caused. "He has ruined so many lives. He must think of the consequences," Jens Breivik said.
On Monday police surrounded the elder Breivik's house in the south of France, to ensure the safety of Breivik after reporters and photographers swarmed to his property.