Philadelphia Ballet (formerly known as Pennsylvania Ballet until its rebranding in 2021) is the largest ballet company in Philadelphia. The company's annual local season features six programs of classic pieces, such as George Balanchine's The Nutcracker, in addition to presentations of new works. The company's artistic director is Angel Corella.

Pennsylvania Ballet was established in 1963 by Barbara Weisberger, a protégée of George Balanchine, through a Ford Foundation initiative to develop regional professional dance companies. The company is considered a cultural institution and is noted for its focus on the Balanchine repertoire.

The company performed nationally for the first time in 1968 at the New York City Center, which led to a decade of national touring, appearances on PBS's Dance in America series, and a stint as the official company of the Brooklyn Academy of Music during the 1970s.

In 1982, Pennsylvania Ballet became the first major American ballet company to promote an African-American woman, Debra Austin, to principal dancer. Between 1987 and 1989, Pennsylvania Ballet forged an alliance with Milwaukee Ballet to create one company. The new organization had 43 dancers, and was the first in the country to offer its dancers year-round employment.

In 1995, Roy Kaiser was appointed as artistic director by the trustees of Pennsylvania Ballet. Kaiser was a former principal dancer and had been hired as a company member in 1979 by Weisberger. Following his retirement from the stage in 1992, Kaiser served as principal ballet master and associate artistic director under Christopher d'Amboise before being named to his current position.

Under Kaiser's leadership, the company expanded its Balanchine-based repertoire to include new works from both established and emerging choreographers. New works included premieres of original ballets from choreographers Merce Cunningham, Christopher d'Amboise, Trey McIntyre, Matthew Neenan, David Parsons, Val Caniparoli, Benjamin Millepied, and Christopher Wheeldon, as well as the 40th-anniversary commission of Swan Lake by Christopher Wheeldon and the 2007 world premiere of Matthew Neenan's Carmina Burana. Pennsylvania Ballet currently employs 37 dancers and annually presents a season of six programs, which includes their annual signature production of Balanchine's The Nutcracker. The season combines classic ballets with new works and challenges the dancers while attracting a diverse audience. The company also tours throughout Pennsylvania and elsewhere, including venues such as New York City Center and the John F. Kennedy Center for the Performing Arts in Washington DC. Pennsylvania Ballet made its international debut at the Edinburgh International Festival in August 2005.

Fourteen members of the Pennsylvania Ballet appeared as the corps in the 2010 film Black Swan. In September 2014, Ángel Corella was named artistic director.

In July 2021, Pennsylvania Ballet rebranded and became the Philadelphia Ballet. The Philadelphia Ballet II (the company's second company) provides outreach and educational performances.