Charles Henry Karius (1893 – 20 September 1940) was an Australian Assistant Resident Magistrate (Kiap) in Australian administered Papua who traversed the widest part of the island from the Fly River in Papua to the source of the Sepik River in New Guinea from December 1926 to January 1928.

After an unsuccessful first attempt in 1926, he succeeded in 1927–28 with second-in-command Ivan Champion and a party of 36 porters and 12 local policemen to traverse Papua from the south coast to the north across the widest part of the country.

He afterwards published an account of the journey in a paper in The Geographical Journal ("Exploration in the Interior of Papua and North-East New Guinea: The Sources of the Fly, Palmer, Strickland, and Sepik Rivers") and Ivan Champion published an account in a book ("Across New Guinea from the Fly to the Sepik").

Charles Karius was awarded the 1929 Royal Geographical Society's Patron's Medal.

[2][3] He died of cancer in Sydney, Australia, in 1940 when on sick leave.