The San Francisco Symphony, founded in 1911, is an American orchestra based in San Francisco, California. Since 1980 the orchestra has been resident at the Louise M. Davies Symphony Hall in the city's Hayes Valley neighborhood. The San Francisco Symphony Youth Orchestra (founded in 1981) and the San Francisco Symphony Chorus (1972) are part of the organization. Michael Tilson Thomas became the orchestra's music director in 1995, and concluded his tenure in 2020 when Esa-Pekka Salonen took over the position.

Among the orchestra's awards and honors are an Emmy Award and 15 Grammy Awards in the past 26 years.

In 1909 the Musical Association (MA) was founded by a group of San Francisco citizens with the goal of establishing a professional symphony orchestra in San Francisco. Among the founding board members of the MA was composer, lawyer, and opera librettist Joseph Redding. Redding played an instrumental role in steering the MA's board during the establishment of the San Francisco Symphony and it is largely through his recommendation that conductor-composer Henry Kimball Hadley was appointed San Francisco Symphony's first principal conductor. Redding also selected the orchestra's first concertmaster, the Dutch violinist Eduard Tak. The governing board of the MA continued to manage the San Francisco Symphony until 1935.

The orchestra's first concerts were led by Hadley in 1911. There were sixty musicians in the Orchestra at the beginning of their first season. The first concert included music by Wagner, Tchaikovsky, Haydn, and Liszt. There were thirteen concerts in the 1911–1912 season, five of which were popular music.

In 1915, Alfred Hertz succeeded Hadley. Hertz helped to refine the orchestra and arranged for the Victor Talking Machine Company to record it at their new studio in Oakland in early 1925. Hertz also led the orchestra during a number of radio broadcasts, including on The Standard Hour, a weekly concert series sponsored by Standard Oil of California. The series began in 1926 when the orchestra faced bankruptcy; Standard Oil of California paid the orchestra's debts and in return was given broadcast rights to that year's concert series. The first broadcast aired on the NBC Pacific Network, on October 24, 1926. and the broadcasts continued for more than 30 years.

After Hertz's retirement in 1930, two conductors, Basil Cameron and Issay Dobrowen, jointly headed the orchestra. During the Great Depression, the Symphony's existence was threatened by bankruptcy and the 1934–35 season was cancelled; the people of San Francisco passed a bond measure to provide public financing and ensure the organization's continued existence. Pierre Monteux (1875–1964) was subsequently hired to restore the orchestra. Monteux succeeded to the point where NBC began broadcasting some of its concerts and RCA Victor offered the orchestra a new recording contract in 1941. In 1949, Monteux invited Arthur Fiedler to lead summer "pops" concerts in the Civic Auditorium. Fiedler also conducted the orchestra at free concerts in Sigmund Stern Grove in San Francisco and the Frost Amphitheater at Stanford University. Fiedler's relationship with the orchestra continued until the mid-1970s.

When Monteux left the orchestra in 1952, various conductors led the orchestra, including Leopold Stokowski, Georg Solti, Erich Leinsdorf, Karl Münchinger, George Szell, Bruno Walter, Ferenc Fricsay, and William Steinberg. Stokowski made a series of RCA Victor recordings with the orchestra in 1952 and 1953.

In 1954, the board hired Enrique Jordá as music director. Surviving eyewitness and newspaper accounts describe him as having youthful enthusiasm, energy, and charm. Jordá sometimes conducted so vigorously that his baton flew from his hand. As the years passed, Jordá reportedly failed to maintain discipline or provide sufficient leadership, resulting in inadequate rehearsal of the orchestra George Szell (1897–1970), the longtime music director of the Cleveland Orchestra, guest-conducted the orchestra in 1962 and was so dismayed by the lack of discipline that he publicly condemned Jordá and even chastised San Francisco Chronicle music critic Alfred Frankenstein for commending Jordá and the orchestra. Szell's comments, along with growing dissatisfaction among musicians and the public, led the symphony board to dismiss Jordá.