He studied with Ferenc Szablya-Frischauf in Budapest and attended the Julian Academy in 1911. It was the works of Cézanne, Braque and Picasso that were the main influences upon him during the year he spent in Paris. He worked in the Kecskemét artists colony from 1912, and joined Lajos Kassák and the activists in 1918. He was a founding member of the New Society of Artists in 1924. He frequently worked in Nagybánya during the twenties, and gradually switched to Szentendre at the beginning of the thirties. A member of the Artists Colony of Szentendre from 1945, he became a teacher of the Hungarian Academy of Fine Arts in 1946, and head of the Painting Department. His autobiographical and theoretical writings are important resource materials for the times.
Bibliography: Kmetty, János: Festő voltam és vagyok. Kmetty János írásai (Művészet és Elmélet), Budapest, Corvina, 1976. o Ury, Ibolya: Kmetty János, Budapest, Képzőművészeti Alap, 1979.