The ComRes opinion poll also found that 63 percent people wanted British troops to be withdrawn as soon as possible, The Scotsman reported.
The survey, illustrating the strength of public feeling against the war, came as a senior British commander in Afghanistan emphasized that maintaining public support is essential for the success of the military mission.
The Deputy Commander of international forces in Afghanistan, Lieutenant General Jim Dutton, said that people needed to understand that British troops were not being sacrificed simply for the sake of the Afghan Government.
The prospect of public and political support for the mission collapsing is understood to be worrying senior commanders.
Britain has 9,000 troops in Afghanistan, while 92 British service personnel have been killed this year in the country, making 2009 the worst year for British forces since the Falklands war.
The total British death toll in the conflict is now 229. Prime Minister Gordon Brown has authorized the deployment of another 500.