According to independent website icasualties.org, the death toll of US-led foreign troops in Afghanistan stands at 565 in 2011, including 417 from the US, 45 from Britain and 32 from Australian defense forces.
The number is down from the wartime high of 711 in 2010 but eclipsed the previous record of 521 set in 2009.
A total of 2,846 foreign troops have died during a decade of occupation of Afghanistan.
The increasing number of military casualties in Afghanistan has caused widespread anger in the US and other NATO member states, undermining public support for the Afghan war.
A United Nations report on Afghanistan issued on September 28 said the average monthly number of security incidents recorded for the year through the end of August rose nearly 40 percent.
The US-led invasion of Afghanistan took place in 2001 under the pretext of combating terrorism, toppling the Taliban regime and establishing security in the country.
However, insecurity continues to rise across Afghanistan despite the presence of nearly 140,000 foreign forces in the country.
Moreover, the killing of civilians by foreign forces has dramatically intensified anti-American sentiments in Afghanistan.
Afghan civilians have paid the highest price in the ten-year-long war. The UN said the number of civilians killed in Afghanistan in the first six months of 2011 rose by 15 percent, compared with the same period in the previous year, to 1,462.
The US-led war in Afghanistan, with civilian and military casualties at record high, has become the longest military conflict in US history.