The managing agent for several Manhattan buildings was busted yesterday for allegedly swindling more than $1 million from his clients.

Mark Modano, the owner of Mark Modano LLC, abused his position by siphoning off cash from six of the dozens of rental and co-op buildings he managed throughout Manhattan in a Ponzi-type scheme, District Attorney Robert Morgenthau said.

Modano, 50, used the cash for personal expenses, including a trip to Italy and theater tickets, prosecutors said.

The alleged swindle hit some of the buildings in more ways than one — in three of the cases, he hadn’t been paying the building’s taxes to the Department of Finance, the DA said.

He agreed to pay in installments in a bid to cover his tracks, but defaulted on those payments earlier this year, the DA said.

The hardest hit was a building at 805 Madison Ave., from which Modano allegedly siphoned off $634,000.

Modano, who pleaded not guilty, faces up to 15 years in prison if convicted.