Famine-driven deaths began to occur across North Korea since late June and the deaths are on the rise this month, a Seoul-based civic group said.
"In the North's east port city of Hamhung alone, some 300 people died from hunger and famine-driven malnutrition in the past month," the agency said in a statement.
About 10 people on average have died every day in every city and town in the North's mountainous northeast provinces of North and South Hamkyong, it said.
The group also said prices of rice and other grains have jumped in the North's markets due to acute shortages.
The aid agency, which has campaigned for poverty reduction in the North, is believed to have a wide range of sources in the communist country.
The report comes as many relief agencies are warning that the North could face its worst food shortages since the mass famines of the mid-1990s that killed approximately 2 million people.