Queensland Police are launching a road safety operation after a sudden increase in pedestrian incidents left five dead and another four injured in less than a month.

Road Policing Command superintendent David Johnson said the number of recent pedestrian deaths was very concerning.

He said pedestrians put themselves at risk when they take shortcuts through areas of the Brisbane City, including walking on the other side of road barriers, around walkways and crossing at red signals.

Queensland drivers will also be investigated as a part of the operation.