Minutes of the Fed's January 29-30 policy meeting, released last week, showed that a number of officials felt the potential risks posed by buying bonds could warrant tapering or ending the program before hiring picks up. However, several others argued there was a danger in halting it prematurely.
Bernanke appeared to be in the latter camp, citing improvements in the housing and auto sectors and tracing them in part to the Fed's stimulus.
In response to the financial crisis and deep recession of 2007-2009, the Fed not only slashed official interest rates to effectively zero but also bought more than $2.5 trillion in mortgage and Treasury debt in an effort to push down long-term interest rates and spur investment.
The Fed is currently buying $85 billion in bonds each month and has said it plans to keep purchasing assets until it sees a substantial improvement in the outlook for the labor market.
In unusually direct remarks on fiscal policy, Bernanke warned that the near-term spending cuts known as the sequester, which are set to take hold later this week, threaten an already challenged economic expansion.
"In terms of the near-term recovery, there's a senses monetary and fiscal policy are working at cross purposes," he said in response to questioning.
"To some extent the fiscal policy decisions being made are mismatched with the timing of the problem," he added. "The problem is a longer-term problem and should be addressed over a longer time frame."
(Read More: Bernanke and Sequestration)
In his prepared remarks, Bernanke said, "The Congress and the administration should consider replacing the sharp, frontloaded spending cuts required by the sequestration, with policies that reduce the federal deficit more gradually in the near term but more substantially in the longer run."
"A substantial portion of the recent progress in lowering the deficit has been concentrated in near-term budget changes, which, taken together, could create a significant headwind for the economic recovery," he said.
The U.S. economy braked sharply in the fourth quarter, but is generally forecast to grow around 2 percent or more this year. Unemployment has remained elevated, and registered 7.9 percent in January.
Bernanke said persistent joblessness was a scourge with potentially long-lasting effects for the United States.
"High unemployment has substantial costs, including not only the hardship faced by the unemployed and their families, but also the harm done to the vitality and productive potential of our economy as a whole," Bernanke said.
— Reuters contributed to this report.