Helmut Zehetner studied violin at the University of Music and Performing Arts in Vienna (MDW) with Franz Samohyl, graduating in 1980. He also studied composition with Friedrich Neumann and conducting with Karl Österreicher and Otmar Suitner, getting his diploma in 1982.

Since 1980, he has been performing as violinist in the Vienna State Opera Orchestra and became a member of the Vienna Philharmonic in 1983. He played as principal of the 2nd violin-section for over 15 years and performed as a soloist and as a conductor with numerous international chamber orchestras.

During his studies, he founded several youth orchestras and organized and held classes at summer academies. Since 1985, he has taught orchestral practice at the MDW. He conducted many concerts with the Webern Sinfonietta and prepared the Webern Symphony Orchestra for conductors like Riccardo Muti, Pierre Boulez, Franz Welser-Möst, Kirill Petrenko, Bertrand de Billy, Claudio Abbado, Mstislaw Rostropovich and Zubin Metha. He established his own musical cycle with the Webern Symphony Orchestra in the Vienna Musikverein.

Since 1997, he has been chairman of the string department at the International Orchestra Institute Attergau, under the patronage of the Wiener Philharmoniker, which gives the chance to skilled students to get in touch with the Viennese sound and playing tradition. In March 2008, he was appointed professor at the MDW.