The number of deaths and serious injuries dropped from 337, in the three years before the cameras were installed, to 108 in the three years to April 2010.
The figures also show that over the same period, on average, personal injury numbers were down 48% (from 1,400 to 684) in areas which have speed cameras or traffic-light cameras, compared with the three years before they were installed.
Scottish safety camera statistics, published by Scotland's chief statistician, also show that the number of speed offences and red-light offences caught on camera has reduced year on year.
In the financial year 2005-06 around 127,000 people were issued with a conditional offer of a fixed-penalty notice as a result of offences recorded on the cameras.
In 2010-11 the figure was around 73,000, although this is up by around 10,000 on the previous 12-month period, attributed to both temporary speed limits at roadworks on major trunk roads and new traffic-light cameras giving greater coverage at existing sites.
Four out of five (82%) respondents to the Scottish Crime and Justice Survey 2010-11 agreed that people should see the use of safety cameras as a good thing.
Fewer vehicles are said to be breaking the speed limit at mobile-camera sites, in all speed-limit categories.
At fixed-speed camera sites, fewer vehicles broke the speed limit at 30mph zones (45% down to 14%) and at 70mph zones (33% to 26%), although more vehicles were caught breaking the limit at 40mph zones (18% up to 22%), 50mph zones (25% to 27%) and 60mph zones (12% to 17%).
Kathleen Braidwood, road safety officer for the Royal Society for the Prevention of Accidents Scotland, said: "We welcome the publication of figures that show reductions in the number of people killed or seriously injured at camera sites. However, it is really disappointing that there has been a percentage increase in vehicles exceeding the speed limit at 40, 50 and 60mph fixed-camera sites, particularly because in Scotland we have so many rural roads that carry these speed limits.
"We know that three out of four road fatalities happen on rural roads. In Scotland, we really need to think about how we are driving on these roads, taking into account the constantly changing environment and what an appropriate speed is for rural roads.
"Safer driving on rural roads means not just travelling within the legal limit but also travelling at an appropriate speed for the conditions."
Around Scotland: the impact of speed cameras
* for the purposes of this graphic a serious accident is one that results in death or serious injury.
* information on fixed penalty notices for different regions begins on different dates. The figure given is for the first full year available.