The Chanel supremo said it was "childish" to even discuss the issue of wearing fur in a world where eating meat was normal.
German-born Lagerfeld, 75, a contemporary of the late Yves Saint Laurent, said that he did not himself wear fur. But he defended the practice, saying there was "an industry who lives from that".
Hunters in the north "make a living having learnt nothing else than hunting", he said, "killing those beasts who would kill us if they could." Animals should be killed "nicely" if at all possible, said Lagerfeld, who admitted to being queasy about eating meat. "I can hardly eat meat because it has to look like something what it was not when it was alive," he said.
He concluded: "In a meat-eating world, wearing leather for shoes and clothes and even handbags, the discussion of fur is childish."
In an interview on the Radio 4 Today programme, Lagerfeld also said the issue of size zero models was insignificant compared to the "zillions" of fat people.
Doctors have criticised the use of size zero models, saying it has contributed to a rise in eating disorders among girls who feel pressured to conform to this idea of beauty. But he said: "In France there are, I think, less than one per cent of people who are too skinny.
"There are nearly 30 per cent of young people who are too fat. So let’s take care of the zillions of the too fat before we talk about the percentage that’s left."
In further questions Lagerfeld said he viewed the global recession as "more like a cleaning up." "It too was rotten anyway, so it had to be cleaned up," he said.
A spokesman for the support group Beating Eating Disorders said Lagerfeld’s comments on size zero models were "a very sad reflection" on attitudes within the fashion industry.
She said: "We talk to thousands of people every year with eating disorders, who say ‘If we look like that, we are told that we should be in hospital.’ Yet these models are being celebrated."
A spokesman for People for the Ethical Treatment of Animals (Peta) described Lagerfeld as a "dinosaur" who had got his facts wrong. She said: "Karl Lagerfeld is a fashion dinosaur who is as out of step as his furs are out of style.
"The vast majority of fur these days comes not from hunters as he suggests, but from Chinese fur farms, where no law protects the millions of animals who are routinely beaten and skinned alive.
"Lagerfeld’s childish refusal to acknowledge the needless suffering behind every piece of fur and listen to public opinion means that he is being overtaken in the style stakes by an increasing number of designers who believe that cruelty has no place in fashion."