The ORF Vienna Radio Symphony Orchestra, known in German as the ORF Radio-Symphonieorchester Wien (RSO Wien), is a prominent Austrian orchestra based in Vienna. Founded in 1969 as the ORF-Symphonieorchester, it is the only radio orchestra in Austria and is part of the national broadcaster Österreichischer Rundfunk (ORF). The orchestra is renowned for its focus on contemporary classical music, distinguishing itself within the Vienna orchestral tradition.

Throughout its history, the Vienna RSO has been led by notable chief conductors, including its first, Milan Horvat (1969–1975), and more recently, Marin Alsop, who took over in September 2019 as the first female chief conductor of the orchestra. Alsop's tenure is set to conclude at the end of the 2025-2026 season, at which point Markus Poschner is expected to take over, pending secure funding.

The orchestra performs regularly at prestigious venues such as the Musikverein and the Konzerthaus in Vienna and is a fixture at major Austrian and international festivals. It has also toured extensively, performing in countries including Japan, China, the USA, and various European nations. The Vienna RSO has a strong reputation in both opera and film music, having collaborated with the Theater an der Wien since 2007 and recorded soundtracks for several films.

In 2023, despite facing proposed budgetary cuts, the Austrian government assured the orchestra's continued existence with secured funding through 2026. The Vienna RSO's performances are frequently broadcast on radio and online, enhancing its international presence.