Campaigning in Florida, the former Massachusetts governor said while Obama may not be responsible for the nation's economic crisis, he is responsible for making it worse, the Los Angeles Times reported.
"It's true you can't blame one party or the other for all the debts this country has, because both parties in my opinion have spent too much and borrowed too much when they were in power," Romney said at a campaign stop.
Romney said rather than fulfilling a promise to cut the debt in half, Obama doubled it.
"I find it incomprehensible that a president could come to office and call his predecessor's record irresponsible and unpatriotic and then do almost nothing to fix it, and instead every year to add more and more and more spending," he said.
Romney did not mention Bush's name Wednesday, referring to him instead as the "predecessor."
The Times said Bush's record on spending issues and the wars in Iraq and Afghanistan is unpopular even within his own party.