Lieberman, who chairs the Senate Committee on Homeland Security and Governmental Affairs overseeing the GSA, said there is no excuse for the organization's excessive spending, especially during a down economy.
"I don't have to say it, but its effect, when the economy is down, when people are struggling to pay their bills, when they're struggling to pay their taxes -- it's outrageous that federal employees did this," Lieberman said in an interview on "Fox News Sunday."
A report by Inspector General Brian Miller revealed region nine of the GSA used taxpayer funds to pay for extravagant conferences and personal travel thinly disguised as government business, CNN said.
In one instance, GSA officials spent more than $800,000 on a conference that included a catered joke awards ceremony.
The senator called for an investigation into region nine as well as the other 10 regions and said he plans to hold hearings to look at the way the GSA does business.
"I mean, this is an agency that is supposed to achieve efficiency in renting, leasing, operating federal buildings. Instead they were wasting money," Lieberman said.
"I get sickened by these kinds of stories from the Secret Service and GSA. They don't reflect what I know to be the typical federal employees, but they do nothing but increase the cynicism that the American -- and anger that the American people feel toward their government. And that's just bad for our democracy," he added.