Martynas Jankus or Martin Jankus (7 August 1858 in Bittehnen (Lit.: Bitenai), near Ragnit – 23 May 1946 in Flensburg, Germany, reburied in Bitenai cemetery on 30 May 1993) was a Prussian-Lithuanian printer, social activist and publisher in East Prussia, called the Patriarch of Lithuania Minor.
He was one of the publishers of Aušra, the first Lithuanian-language newspaper for both Lithuania Minor and Lithuania Major.
Jankus used various pen names, including V.
Giedris, Martyneitis, Bitenu Mercius, and Gyvoleitis.