Bernanke, speaking at the University of Michigan, says the approaching debt limit is one of the "critical fiscal watersheds" for the government in coming weeks.
President Barack Obama also spoke Monday about the urgency of raising the limit. Obama said he wouldn't let congressional Republicans use the debt limit as leverage in negotiations over spending cuts.
Bernanke notes that an impasse over the debt ceiling in 2011 led to a rating downgrade of long-term U.S. debt, the first time that's occurred.
He says Congress should raise the ceiling to "avoid a situation where our government doesn't pay its bills."