Harald Rolf Maartmann (5 January 1926 – 1 January 2021) was a Norwegian cross-country skier who competed in the 1950s. He won both the 17 km and the 50 km event in the Norwegian Championships in 1950. He finished fifth in the 50 km event at the 1950 World Championships in Lake Placid, New York. Maartmann also finished eighth in the 50 km event at the 1952 Winter Olympics in Oslo.