The percentage of missions in which drones have used weapons also doubled between 2008 and 2012, data released by Defence Minister Andrew Robathan in a written parliamentary answer showed.
In 2008, there were 296 missions over Afghanistan and one or more missiles was deployed by a British-operated Reaper drone on 14 missions, 5% of the total number of sorties.
But in 2012, there were 892 missions by British drones, with weapons being fired on 92 occasions - more than 10% of all sorties.
The figures are likely to alarm campaigners who say it is too difficult to hold governments to account for the use of drones.
The United States has also faced opposition to their use in Afghanistan and Pakistan in the war against international terrorism. But last year, Government minister Baroness Warsi told the Lords the UK had not used drones in Pakistan.
In October last year, the Government announced it was doubling the number of armed Reaper drones to 10, with the new aircraft being operated remotely from RAF Waddington in Lincolnshire.