Erik "Eero" Nikolai Järnefelt (8 November 1863 – 15 November 1937) was a Finnish painter and art professor. He is best known for his portraits and landscapes of the area around Koli National Park. He was a medal winner at the Paris "Exposition Universelle" of 1889 and 1900, and he taught art at the University of Helsinki and was chairman of the Finnish Academy of Fine Arts.