The Sri Lankan government had requested $1.9 billion loan from the IMF in March, two months before the government troops defeated Tamil Tiger rebels.
Economists said the end of the 30-year-old conflict provides Sri Lanka with an opportunity to undertake economic reform and reconstruction that would be crucial for higher economic growth.
The government is hoping that the island's economy would grow by between 3.5 to 4.5 percent in 2009 despite the prevailing global financial crisis.
Sri Lanka joined the IMF in 1950 and has a quota of about $644.4 million.