According to the PAC, the government spends £3bn every year on new builds or refurbishments.
Chairman of the PAC, Edward Leigh MP, said: "The government is a long way off meeting its own targets and standards for the sustainability of its buildings.
"Environmental assessments of new government buildings are supposed to be mandatory but are actually being conducted in only a third of cases. And fewer than a one in ten of such projects can be shown to meet the required environmental standards," he said.
"The government should practice what it preaches and set an example for others to follow.
The PAC say the Treasury, DEFRA and the Office of Government Commerce (OGC) should lead and advise departments on adopting sustainable building methods, and a light version of the Building Research Establishment's Environmental Assessment Method (BREEAM) should be developed for smaller builds.
"It goes without saying that the systems for monitoring compliance with environmental standards are poor and that there is no overall responsibility for making sure that fine words about greener government buildings are translated into action," said Leigh.
The report says government departments opt for initial cost-savings rather than look at overall life-costs, and are making poor progress with environmental targets for estate management.
However Leigh said, "The picture is not all bad – with a fifth of all new builds examined by the National Audit Office achieving an excellent environmental rating. But departments in general are clearly taking a cavalier approach to the sustainability of their new buildings.
"The message must be driven home that sustainability can and should deliver better value for money over the whole lifetime of a building. I welcome action by the Treasury to simplify the mechanisms for estimating the cost of a building over the whole of its life. It now needs to make sure that departments use them."