Mesogona oxalina is a moth of the Noctuidae family. It is found in southern and central Europe, north to Fennoscandia, east to the Baltic States and Russia (up to the Ural), south to the Iberian Peninsula, Italy and Greece. The wingspan is 34–39 mm. Adults are on wing from August to September depending on the location. The larvae feed on Alnus, Populus, Prunus and Salix species.