Managing Director Christine Lagarde said the move made the Fund the first multilateral institution to help ease the debt burdens of Liberia, Sierra Leone, and Guinea, and said others needed to follow suit.
"I'm calling on the international creditors to also consider debt relief to these three countries," Lagarde said.
The IMF has already received a commitment to that end from one major donor, she added.
"I hope that they will not be the only one."
The Ebola outbreak, which began a year ago, has killed around 9,000 people mostly in the three countries, and savaged their economies and government finances.
The IMF and World Bank have repeatedly warned that the countries need more support, including loan writeoffs, to be able to focus on restoring growth.
"Our membership has demonstrated great commitment in coming together to respond to the Ebola crisis," Lagarde said.
The IMF's debt relief will come under a new Catastrophe Containment Relief Trust. It will provide the three countries with USD 100 million to cover their debt-service payments to the IMF over the next two years.
The trust will be a permanent fund to help countries beset by large natural disasters like epidemics and massive earthquakes.
It will replace the Post Catastrophe Debt Relief Trust organized to support Haiti after its devastating 2010 earthquake. That trust's mission was not broad enough to include epidemics.