The nation's parliament house is under attack from clothes-eating moths.

The Department of Parliamentary Services has warned infestations of casemaking moths have been detected in parts of the building.

"We are asking that all building occupants remain vigilant in keeping an eye out for signs that casemaking moths may be present," it said.

Usually found in carpet or clothing, the moths "are very fond of organic fabrics" and, in particular, can be found under furniture and artwork plinths.

Moth traps have been installed and photos of the moths distributed to aid identification.

Cleaning staff are investigating.