Canberra drivers can expect to see more speed cameras, more often on local roads, as the ACT Government expands the number sites where mobile speed cameras will operate from today.

The changes, a part of the Government's road safety strategy, will see more cameras placed in school zones and accident hotspots around Canberra.

Under previous regulations, mobile units could only be used at selected locations.

Justice Minister Shane Rattenbury said at least 30 new locations will be trialled by the end of next month.

"Unfortunately speeding is a factor in one third of all fatal accidents on ACT roads and so it is something we need to tackle," he said.

"There'll be a focus on black spots also based on police information and then just random places to make sure that message really gets across that there will be speed cameras out there anytime, anywhere matched with increased resources to give our vans more time on the road."

Mr Rattenbury said mobile speed camera vans will be out on the roads up to an extra 120 hours per week.

"With the increase in the amount of hours that the speed cameras can be out there and also an increased number of locations, Canberrans can expect to see the speed vans more often," he said.

"I really do hope that will encourage people to slow down and follow the speed limit."

This year's ACT budget included $1.3 million in funding over four years to increase mobile speed camera operations.