Christiane Amanpour in an interview that aired Friday.
"It is a common threat for all of us," he said. "And this requires a unison effort from all of us."
"We need a vast campaign of operations ... the aerial bombardment campaign is mostly, I would say, a form of theater, rather than a serious battle against terrorism."
Iran and the United States have found their foreign policies surprisingly aligned in the past several months, as both try to beat back the advance of the Sunni extremists that have gained a foothold in Iraq and war-torn Syria.
While the United States has limited itself thus far to airstrikes in those two countries, Iran has sent Revolutionary Guard units into Iraq; the head of the Revolutionary Guard's Quds Force, Qassem Suleimani, has even been photographed on the ground in Iraq.
Five Gulf countries, traditional adversaries of Shiite Iran, joined with the United States in a rare coalition to strike ISIS in Syria.
However, Rouhani said he'd like to distance himself "from the word 'coalition' because some countries haven't come together under the umbrella of this coalition."