The United Nations says North Korea has asked for food and fuel aid to be made available.
Flooding in July submerged vast areas of North Korea's farmland, killing more than 100 and ruining crops.
UN officials in Pyongyang said the need for aid was urgent after visiting flood-hit parts of the country to assess damage.
North Korea state media said that at least 119 people died and tens of thousands were left homeless.
Damage to infrastructure and farmland has affected the country's already dire food shortage problem.
The most badly affected areas are Anju city and Songchon County in South Phyongan Province and Chonnae County in Kangwon Province the UN says.
Residents in these areas are in urgent need of food supplies, as well as clean water, as wells have been contaminated by sewerage during the floods.