Storms caused some $1bn in damage to Haiti in 2008
Bill Clinton has been named by the United Nations as its special envoy to Haiti, to boost social and economic recovery in the Caribbean state.
Mr Clinton said he was honoured to accept the position.
He said he would work to help Haiti rebuild after last year's tropical storms which killed nearly 800 people and caused $1bn (£660m) in damage.
The ex-leader helped raise funds for Haiti recently, and is seen as having an enduring interest in the country.
Announcing the post, UN chief Ban Ki-Moon said: "I am confident that President Clinton will bring energy, dynamism and focus to the task of mobilising international support for Haiti's economic recovery and reconstruction."
In March, Mr Clinton visited the country with Mr Ban, spurring a global fundraising effort which raised more than $300m for the rebuilding effort in Haiti, the poorest country in the Americas.
"Last year's natural disasters took a great toll, but Haiti's government and people have the determination and ability to build back better, not just to repair the damage done but to lay the foundations for the long-term sustainable development that has eluded them for so long," Mr Clinton said in a statement.
Because of Mr Clinton's marriage to US Secretary of State Hillary Clinton, US state department lawyers must authorise his new role.
Haiti does not currently have a special UN envoy.
The Miami Herald, which first announced the appointment, said he would be expected to visit the Caribbean country at least four times a year.
He will be paid $1 per year, reports AP news agency.