Sir Richard Branson has urged the government to take responsibility for drugs policy away from the Home Office and treat misuse as a "health issue".
The entrepreneur told the Commons home affairs committee this could bring a fall in use, saying such a policy had worked in Portugal and other countries.
He said Prime Minister David Cameron had to be "brave" over the issue.
But Sir Richard added: "I would not advocate heroin and cocaine to be sold in supermarkets."
In the first evidence session for the committee's inquiry into drugs policy, he said that treating drug misuse as primarily a health issue would cut deaths from Aids and reduce addiction levels.
Virgin boss Sir Richard, who is a commissioner for the Global Commission on Drug Policy, said: "The Home Office can concentrate on organised crime and the health department can concentrate on people with drug problems."
This would be a "win-win all round", he added, citing the example of Portugal, where no drug user had been sent to prison for 10 years.
Sir Richard said this had cut the level of people taking heroin by 50% and allowed a greater focus on catching the criminals supplying substances.
He also said that greater regulation of the drugs trade would mean young people have a better idea of what they are taking, cutting deaths.
Some 100,000 people were arrested in Britain each year, with 75,000 of them being given criminal records, Sir Richard added.
This meant "it might be difficult to travel and get passports to certain countries".
Sir Richard said: "By actually moving drugs into the health department and not in the Home Office, if people have a problem, just like in Portugal, they should go in front of a panel to help them."
The committee's previous inquiry in 2002, when David Cameron was on the committee, said drug use was a "passing phase" for many young people which "rarely results in any long-term harm".
The cross-party group dismissed legalisation and decriminalisation but urged ministers to lobby for the loosening of international treaties which prohibit such radical steps.
Speaking more than 10 years ago, Mr Cameron added that the UK's drugs policy had "been failing for decades" and he hoped the report would "encourage fresh thinking and a new approach".
Addressing the MPs, Sir Richard said: "David Cameron wasn't prime minister [then] and now he has become prime minister, and we hope that we can give him the information to make him brave in changing drugs policy for society as a whole."
But the Home Office has said it has "no intention of liberalising our drugs laws".