Lars Erik ("Lasse") Dahlquist (14 September 1910 in Örgryte (grew also up in Lidingö) – died 14 October 1979 on Brännö, Gothenburg archipelago due to laryngeal cancer) was a Swedish composer, singer and actor. Many of his songs are among the most popular sing-along songs in Sweden, such as Oh boy oh boy oh boy and Gå upp och pröva dina vingar.

He was married to Inez Margareta Dahlquist, née Lindquist (1911–2004) from 1936 and they had a son; the saxophonist Robert "Bob" Dahlquist (2 September 1938 – 6 September 2005). On Saltholmen, at the terminal of the boats of Styrsöbolaget, there is a place called Lasse Dahlquists Plats.

As a child, he spent his summers at his grandfather's farm, Langegården, on Brännö where he built his own home as well.

He worked at Sven-Olof Sandberg's music publishment Svenska Noter and in 1931 he began recording gramophone records.

In 1977 he received the Evert Taube award.