William "Willy" Larsen (November 18, 1885 – March 10, 1935) was a Finnish American accordionist and director.

[1] Larsen's ancestors came to Finland from Norway in the 17th-century, and he was born in Kotka.

As a young man Larsen became a sailor and moved to the US before World War I.

He settled down in New York City, where he performed at the Finnish American halls.

[2] He also made several recordings as accompanist for various artists, including Leo Kauppi and Hannes Saari.