The Luxembourg Philharmonic Orchestra (in French, Orchestre philharmonique du Luxembourg) is the leading symphonic ensemble of that small northwestern European nation.

The orchestra was one of a group of symphonic ensembles whose origins were connected with the rise of radio; it was founded in 1933 as the orchestra of the national RTL broadcaster and was named the RTL Grand Symphony Orchestra (Grand orchestre symphonique de RTL). The orchestra was organized by Henri Pensis, who served as music director until 1939, then fled to the U.S. when Germany incorporated Luxembourg at the beginning of World War II, and returned to the liberated country in 1946, remaining in his post until his death in 1958. Other major conductors from the orchestra's early years were Louis de Froment (1958-1980), Leopold Hager (1981-1996), and David Shallon, who died in 2000 while the orchestra was on tour. In the 21st century, the orchestra's conductors have been drawn from international ranks: Bramwell Tovey served as music director from 2001 to 2006, and Emmanuel Krivine from 2006 to 2015. That year, Gustavo Gimeno took over the baton.

The Luxembourg Philharmonic in the 1990s faced the removal of its primary funding source: RTL, having been privatized by the Luxembourg government, ended its relationship with the orchestra in 1995. The government established the Pensis Foundation the following year as a funding mechanism, and the orchestra's finances stabilized. The group gives concerts at the Philharmonie Luxembourg concert hall, which opened in 2005.

Beginning in the mid-1990s with a recording of music by Jean Cras, the Luxembourg Philharmonic has amassed a large catalog of music on France's Timpani label. Most have been devoted to French music, but these include a five-volume cycle of the orchestral music of Iannis Xenakis. In 2017 the orchestra moved to the Dutch audiophile label PentaTone, where it has essayed broader mainstream repertory, such as Bruckner's Symphony No. 1 and, in 2018, Mahler's Symphony No. 4 in G major. ~ James Manheim, Rovi