The Edmonton Symphony Orchestra (ESO) is a Canadian orchestra based in Edmonton, Alberta. As the professional orchestra of Alberta's creative capital city it presents over 85 concerts a year of symphonic music in all genres, from classical to country. Currently in its 74th season, the orchestra is composed of 56 core professional musicians who perform 42 weeks per season and who play an active role in the musical life of Edmonton and elsewhere as performers, teachers and recording artists. The ESO also performs as the orchestra for Edmonton Opera and Alberta Ballet productions, and its recordings are regularly heard across Canada on CBC Radio 2.

The Edmonton Symphony Orchestra was initially formed as Edmonton's community orchestra and performed its first concert on November 15, 1920. The orchestra suspended operations in 1932 due to lack of funds, but was revived on October 31, 1952, when it was incorporated as a registered not-for-profit organization (the Edmonton Symphony Society), and gave its first performance on November 30, 1952. It made the transition to a fully professional orchestra in September 1971. In 1973, it was decided to restrict the orchestra to "classical" size.

Prior to the COVID-19 pandemic, the ESO's budget was over $10 million, and its players were the highest-paid Canadian orchestral musicians west of Toronto.

In September 1997, the Edmonton Symphony Society and the Edmonton Concert Hall Foundation successfully completed a two-decade, $45 million capital campaign, and the ESO moved from the Northern Alberta Jubilee Auditorium (the orchestra's principal performing venue since 1957) into its new concert hall, the acoustically superb, 1716 seat Francis Winspear Centre for Music. The inaugural gala, at which the ESO performed Mahler's Symphony of a Thousand with the Calgary Philharmonic Orchestra, took place on September 13, 1997.

Each season, almost 30,000 students experience the orchestra's music at the Winspear Centre. The Young Composers Project, with local composers as mentors, allows select high school students to compose orchestral works and hear them in performance. The orchestra's annual outdoor Symphony Under the Sky Festival is a popular destination for Edmontonians on Labour Day weekend.

The ESO's history and the varied nature of its programming reflect its imaginative commitment to its community.

Special ESO concerts drawing sold-out houses have featured, among others, k.d. lang in 1985, Tom Cochrane and Red Rider in 1989, The Arrogant Worms in 2002, Corb Lund in 2005, Paul Brandt in 2006, Video Games Live in 2007, Nikki Yanofsky in 2008, reunion concerts with Procol Harum in 1992 and 2010, Ben Folds in 2012 and 2014, and Ian Tyson on the 100th anniversary of the Province of Alberta on September 1, 2005. In March 2011, the ESO presented a memorable concert devoted exclusively to the music of Frank Zappa, and in December 2005, the orchestra returned to the Northern Alberta Jubilee Auditorium to present two sold-out Christmas concerts with Christian singer/pianist Michael W. Smith. The orchestra continues this tradition of working with musicians from a variety of musical genres. In December 2012, the orchestra performed two Christmas concerts with the Barenaked Ladies. In December 2017, the orchestra performed four Christmas concerts with Jann Arden.

John McPherson was the orchestra's fourth Composer in Residence (2016–2017) and wrote two major works during his residency: