Sakari ”Saku” Kuosmanen, born in 1956 in Helsinki, Finland, is a Finnish singer and actor. His musical career included playing guitar and vocals for Juice Leskinen Grand Slam on the 1985 album Pyromaani palaa rikospaikalle, as well as work with Sleepy Sleepers and Leningrad Cowboys. His solo discography began with the album Sakari Kuosmanen in 1985, followed by Löytötavaratoimisto "Ep" and Ihana elämä in 1986, and Suurin onni in 1989. In the 1990s, he released Kuu ja Kulkija in 1995 and Yö katseessasi in 1999. His later works include the compilation Onnen lyhteitä – 32 kulkijan laulua in 2001, and the albums Pieni sydän in 2002, Entä jos... in 2003, Suojaton in 2006, and Arkipäivän Jeesus in 2023. Parallel to his music, he is a frequent actor for director Aki Kaurismäki, appearing in films such as Calamari Union in 1985 and Mies vailla menneisyyttä in 2002.
