"I know them both ... it comes down to one thing: leadership. Mitt Romney would be a much better leader. We need a strong leader today," Quayle said on NBC's "Today" show Thursday.
The former vice president announced his endorsement of Romney at a press event in Arizona Tuesday, where he praised the former Massachusetts governor's conservative values.
"Mitt Romney is the one that can bring the party together. He can go into the general election against President Obama. He can expand the base," Quayle added.
Qualye, who served in the Congress with Gingrich, was critical of the former House Speaker's record as a Washington insider.
"Washington is a mess. It's dysfunctional. It starts at the top. There's a lot of blame to go around, but somebody from inside Washington, some Washington politician, somebody who has been there for the long time in Washington, D.C., is not the one to have the top job to try to clean up this mess," Quayle said.
However, when asked whether Gingrich could win in a general election against Obama, Quayle responded without hesitation, "Yes."