The Unknown Soldier (Finnish: Tuntematon sotilas) is a Finnish film from 1985 directed by Rauni Mollberg. It is based on the best selling Finnish novel by the same name written by Väinö Linna. It is the second film adaptation of Linna's novel, the first one being the 1955 film of the same title, directed by Edvin Laine. Third film adaptation of the same novel was released in 2017, directed by Aku Louhimies.

It was screened in the Un Certain Regard section at the 1986 Cannes Film Festival. The film was selected as the Finnish entry for the Best Foreign Language Film at the 59th Academy Awards, but was not accepted as a nominee. The film received three Jussi Awards: Mollberg for directing and actors Risto Tuorila as Koskela and Paavo Liski as Rokka.