Iosif Dailis (6 October 1893–7 December 1984) was a Romanian and Moldavian Soviet violinist, violist, and music teacher. Born in Chisinau, he was one of eight children in the family of Leon Dailis, a private attorney and public figure, and Rosa Dailis.
From 1902 to 1913, he studied at a private music school in Chisinau and at the local music college of the Russian Musical Society, where he studied violin with Iosif Finkel. He later specialized at the Brussels Conservatory with Cesar Thomson in 1913–1914 and continued his studies with G. Herman at the Geneva Conservatory from 1915 to 1917. While in Geneva, he also studied economics at the university.
After returning to Chisinau in 1917, Dailis taught at the Chisinau Music College and the private Unity Conservatory. From 1918 to 1922, he performed with the Bessarabian Opera orchestra. Between 1920 and 1940, he was concertmaster and soloist with the orchestra of the Union of Cultural Societies of the Bucharest Royal Philharmonic. He was also a soloist with the Bucharest Conservatory Symphony Orchestra from 1926 to 1940 and the Bucharest Radio Symphony Orchestra from 1934 to 1940, and concertmaster of the Bucharest Opera orchestra, conducted by Egizio Massini.
In 1940, Dailis returned to Chisinau and became a professor and head of the wind instruments department at the newly established state conservatory. During the war, he performed in hospitals with a chamber ensemble. After the conservatory reopened, he led its string instruments department until 1953 and continued teaching there until 1968. His students included Z. M. Tkach, G. A. Shirman, Nukhim (Naum) Loznik, E. S. Kletinich, S. A. Lunkevich, Yu. Bershadskaya, P. B. Rivilis, M. Tzinman, L. Gavrilov, L. Goncharuk, I. Ponomaryova, E. Bessonova, L. Bachinin, G. Saulescu, E. Kodryanskaya, I. Giledansky, and S. Sokolskaya. His memoir, Life and Music, was published posthumously in 1992.