Polish Legion in Finland (Polish: Legion Polski w Finlandii, Finnish: Puolan Legioona Suomessa, Russian: Польский Легион в Финляндии) was a military unit made up of ethnic Poles who had been soldiers of the Russian Imperial Army during World War I and stationed in the Grand Duchy of Finland. Created on April 24, 1917, in Viipuri, the unit existed until March 1, 1918. It comprised an infantry battalion in Viipuri, an infantry company in Ino, and a heavy artillery battery in Sveaborg. At its peak, the Legion comprised 37 officers and 1,700 soldiers and was commanded by Captain Stanisław Bogusławski.

The Legion, based in Viipuri, as well as other Finnish towns, such as Helsinki, Ina, Lappeenranta, Tampere, Vaasa, Turku, Oulu, Tornio, Hämeenlinna, Kokemäki, Rauma, Panelia (Kiukainen), Riihimäki, Kotka, Mikkeli, Pori and Hanko, was subordinate to the Government of Finland, and took part in fighting against Red Army troops during the Finnish Civil War, capturing large amounts of equipment, which was handed to the Finnish Army.