The cultivation area in 2011 reached 324,000 acres, compared to 304,000 acres in the previous two years, an increase of seven percent, the United Nations Office on Drugs and Crime (UNODC) said in a report.
The amount of opium produced has risen from 3,968 tons in 2010 to 6,393 tons in 2011, an increase of 62 percent.
Last year's report showed a serious decline in poppy production, attributed to a disease that ravaged the crop. But production has returned to pre-2010 levels, the UNODC said.
"The Afghan Opium Survey 2011 sends a strong message that we cannot afford to be lethargic in the face of this problem. A strong commitment from both national and international partners is needed," UNODC executive director Yury Fedotov said.