The Battle of Dumpu was an action fought in September and October 1943 between Australian and Japanese forces in New Guinea during the Markham and Ramu Valley – Finisterre Range campaign of World War II. After the Battle of Kaiapit on 20 September 1943, in which the 2/6th Independent Company won a victory against a numerically superior Japanese force, Ivan Dougherty's 21st Infantry Brigade of the 7th Division advanced from Kaiapit to Dumpu in the Ramu Valley.