Afghan President Hamid Karzai will open the event, aimed at eradicating the drugs trade and exploring alternatives means of production for Afghan poppy farmers.
It comes a day after Afghan authorities publicly burnt 20 bags of poppies in Kabul.
Afghanistan has cracked down on the drugs trade in recent months, after a revival in opium production followed the collapse of the puritan Taleban regime.
Afghan Interior Minister Taj Mohammed Wardak said more drugs would be burnt as they were found.
"There will be a concerted strategy to eradicate this menace," he said.
About 200 spectators gathered to watch as Afghan soldiers set fire to the poppies, which produce opium, the raw material for heroin.
Opium revival
Mr Wardak said Afghanistan would never be accepted by the international community as long as it supplied the West with heroin.
Opium production was virtually wiped out under the Taleban, who declared narcotics to be "un-Islamic".
But the trade has flourished in parts of Afghanistan again since the former regime was vanquished last year.
Last October, the United Nations said the main areas of opium production were in areas under the control of the anti-Taleban Northern Alliance.
Anti-drug authorities said farmers also swiftly revived opium cultivation in areas which had been under the Taleban's control.
"The farmers kept their seeds," one Afghan official told French news agency AFP. "They were just waiting for the right time to plant them," he said.
Trafficking
According to the UN two years ago, 70% of heroin in western Europe originated in Afghanistan.
In some rural areas, where farmers are more answerable to local warlords than central government, smoking opium is considered an acceptable past-time.
"If Kabul sends someone to burn down their crop, there is likely to be trouble," an Afghan official told AFP.
"It is much better to have an educated approach that will trickle down to the farmers. They need incentives to grow other crops," he said.
Afghanistan does not suffer a major drug abuse problem, although there has been a rise in the number of drug addicts in Afghan refugee camps in neighbouring Iran and Pakistan.