Jan Kubis said that despite the good news of a fall in annual civilian casualties in Afghanistan - the first decline in several years - the casualties of women subjected to violence are on the increase.
The United Nations said last month that more than 300 women and girls were killed and more than 560 injured during 2012.
"The majority is linked to domestic violence, traditions, culture of the country," Kubis told reporters at the United Nations in New York ahead of a debate on Afghanistan by the UN Security Council on Tuesday.
"Of course there are very clear attacks on women activists by the insurgency," he said. "Then there are unfortunate situations when indeed women are killed while doing their daily chores."
The UN political mission in Afghanistan, led by Kubis, said in December that Afghanistan still had a long way to go in implementing the 2009 Law on the Elimination of Violence against Women, which made child marriage, forced marriage, rape and other violent acts criminal offenses.
"Our role as the UN will be very crucial in the post-2014 period," Kubis said. "We will be one of the promoters, advocates of what should be practices in a country that will be perhaps more traditional and will be coming back to its roots."
"The situation is a concern and will remain a concern," he added.
