The study says that Afghanistan's biggest donor, USAID, allocates close to half of its funds to five large US contractors and that "it is clear that substantial amounts of aid continue to be absorbed in corporate profits."
The five companies are KBR, the Louis Berger Group, Chemonics International, Bearing Point and Dyncorp International, the report said.
The report, which was written by Oxfam, a British charity, said the cost of a full-time expatriate consultant working in Afghanistan is around $250,000. It is some 200 times the average annual salary of an Afghan civil servant, who is paid less than $1,000 per year.
Mohammed Hashim Mayer, ACBAR deputy director, said that both rural and relatively secure areas are being neglected.
"The donations are spent mostly in cities, not villages, while most people live in villages," Mayar says.
"They are spent in areas where security is not good, hoping that it will improve there. But the opposite is happening. We have seen that security didn't improve in those areas, but worsened instead. In areas where there are possibilities of [implementing projects], no work is being done."
Jim Kunder, acting deputy administrator of USAID, said he recognised there are always concerns about the speed in which aid is delivered but he said the envisioned work is being done.
USAID said it had pledged $25.8 billion, and of that $17.4 billion has been spent or is in the pipeline. Kunder said the money has gone to a broad variety of projects, including "supporting the national elections, constructing roads, reducing infant mortality by 22 per cent, putting more than 4 million Afghan children in schools."
Previous reports by aid groups have said the international community is spending far less aid money in Afghanistan per capita, putting far fewer soldiers on the ground than it has in previous conflicts.
In the two years following the US-led invasion, Afghanistan received $57 per capita in aid, while Bosnia and East Timor received $679 and $233 respectively, the report said.
Spending on development is dwarfed by that spent on fighting the Taliban, in which the US military is spending $65,000 a minute, Oxfam said.
Violent incidents are up at least 20 per cent since last year, according to UN estimates, and have spread northwards to many areas previously considered safe.
More than 200 civilians have been killed in at least 130 Taliban suicide bombs and at least 1,200 civilians have been killed overall this year, about half of them in operations by Afghan and international troops.
Oxfam called on the 50,000 foreign troops in Afghanistan to take greater care not to hurt civilians, particularly in air attacks.