He faced off Ed Miliband who described his successor's manifesto as "more radical than mine" – but one he was proud to endorse.
Mr Duncan Smith labeled Labour's manifesto "utterly irresponsible" and accused Corbyn of running an "anything you want campaign".
During the exchange, the former Tory cabinet minister said Labour had not learned from their past mistakes as he cited the economic state when Labour last left office.
Iain Duncan Smith condemned the Labour party as economically illiterate in a blistering attack
Ed Miliband rushed to Mr Corbyn's defence
He told Radio 4: "When Labour were last in office they left us with no money, and one of the world's worst financial collapses in history.
"Corbyn is approaching this election and just accepting his economics don't add up. You tax and damage the work and jobs and houses people own.
"We all know where this leads. You end up like Greece, where the bankers are telling you what to do."
The former Conservative leader warned that a Labour government would oversee the biggest hike in taxes since the 1940s.
However, Ed Miliband rushed to Mr Corbyn's defence, pointing to Labour's surge in the polls as proof that the leader was "in tune" with the public mood.
He added: "We have had seven years of austerity and cuts to the health services, cuts to education. It has failed.
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"The Tories even know it has failed. This is an emergency as far as our public services are concerned."
Iain Duncan Smith defended his party's campaign
We all know where that leads. You end up like Greece, where the bankers are telling you what to do
Iain Duncan Smith
Mr Miliband continued: "The Conservatives first said the deficit would be gone by 2010, then it was 2017, and now the target it 2025.
"The Conservatives has completely failed Britain!"
But, the Tory candidate then jumped in to hit out at the "hypocrisy" of Labour criticising others of financial mismanagement.
He said: "Remember the note, Ed! No money left in the bank.
"There was no money when you left last time, and that is exactly what will happen again."