Figures released from the Keep Australia Beautiful Rural Highway Litter Index 2013-14 showed NSW had dropped from third to fourth when it came to ranking Australian states on littering on country roads.

Keep Australia Beautiful chief executive officer Peter McLean said people in NSW threw out 10 more items of rubbish out of their vehicles on highways and back roads than they did during the 2012-13 study.

"NSW has increased from 24.2 to 35.7 items of litter out of the car for every 1000 square metres of highway," Mr McLean said.

The most common rubbish items were plastics, cigarette butts, paper and glass.

According to the figures, Victoria was the cleanest state with 5.7 items per 1000 square metres, up on their 2012-13 rate of 3.9 items.

South Australia came in next, followed by Tasmania then NSW, with Queensland travellers listed as the worst having dumped 53.2 items per 1000 square metres.

Dubbo mayor Mathew Dickerson said he had not noticed an increase of visible rubbish on the roads leading out of Dubbo.

"There has certainly been comments made and the council is conscious of it," Cr Dickerson said.

"The best way for Dubbo and surrounding towns to combat the issue would be for everyone to do their bit."

Cr Dickerson said the changes did not need to be drastic, more so people cleaning up after themselves.

"If everyone pulls in together, it could make a huge difference," Cr Dickerson said.