Peking opera, or Beijing opera (Chinese: 京劇; pinyin: Jīngjù), is the most dominant form of Chinese opera, which combines instrumental music, vocal performance, mime, martial arts, dance and acrobatics. It arose in Beijing in the mid-Qing dynasty (1644–1912) and became fully developed and recognized by the mid-19th century. The form was extremely popular in the Qing court and has come to be regarded as one of the cultural treasures of China. Major performance troupes are based in Beijing, Tianjin and Shanghai. The art form is also preserved in Taiwan, where it is also known as Guójù (Chinese: 國劇; lit. 'National opera'). It has also spread to other regions such as the United States and Japan.

Peking opera features four main role types, sheng (gentlemen), dan (women), jing (rough men), and chou (clowns). Performing troupes often have several of each variety, as well as numerous secondary and tertiary performers. With their elaborate and colorful costumes, performers are the only focal points on Peking opera characteristically sparse stage. They use the skills of speech, song, dance and combat in movements that are symbolic and suggestive, rather than realistic. Above all else, the skill of performers is evaluated according to the beauty of their movements. Performers also adhere to a variety of stylistic conventions that help audiences navigate the plot of the production. The layers of meaning within each movement must be expressed in time with music. The music of Peking opera can be divided into the xīpí (西皮) and èrhuáng (二黄) styles. Melodies include arias, fixed-tune melodies and percussion patterns. The repertoire of Peking opera includes over 1,400 works, which are based on Chinese history, folklore and, increasingly, contemporary life.

Traditional Peking opera was denounced as "feudalistic" and "bourgeois" during the Cultural Revolution (1966–1976) and replaced mostly with the revolutionary operas until the period's end. After the Cultural Revolution, these transformations were largely undone. In recent years, Peking opera has responded to sagging audience numbers by attempting reforms, including improving performance quality, adapting new performance elements, shortening works, and performing new and original plays.

"Peking opera" is the English term for the art form; the term entered the Oxford English Dictionary in 1953. "Beijing opera" is a more recent equivalent.

In China, the art form has been known by many names at different times and places. The earliest Chinese name, Pihuang, was a combination of the xipi and erhuang melodies. As it increased in popularity, its name became Jingju or Jingxi, which reflected its start in the capital city (Chinese: 京; pinyin: Jīng). From 1927 to 1949, when Beijing was known as Beiping, Peking opera was known as Pingxi or Pingju to reflect this change. Finally, with the establishment of the People's Republic of China in 1949, the name of the capital city was reverted to Beijing, and the formal name of this theatre in mainland China was established as Jingju. The Taiwanese name for this type of opera, Guoju, or "national opera", reflects disputes over the true seat of the Chinese government.

Peking opera was born when the Four Great Anhui Troupes brought Hui opera, or what is now called Huiju, in 1790 to Beijing, for the eightieth birthday of the Qianlong Emperor on 25 September. It was originally staged for the court and only made available to the public later. In 1828, several famous Hubei troupes arrived in Beijing and performed jointly with Anhui troupes. The combination gradually formed Peking opera's melodies. Peking opera is generally regarded as having fully formed by 1845. Although it is called Peking opera (Beijing theatre style), its origins are in the greater areas of the capital of Anhui province (the City of Anqing), including southern Anhui and eastern Hubei, which share the similar dialect of Xiajiang Mandarin (Lower Yangtze Mandarin). Peking opera's two main melodies, Xipi and Erhuang. Xipi literally means "skin puppet show", referring to the puppet show that originated in Shaanxi province. Chinese puppet shows always involve singing. Much dialogue is also carried out in an archaic form of Mandarin Chinese, in which the Zhongyuan Mandarin dialects of Henan and Shaanxi are closest. This form of Mandarin is recorded in the book Zhongyuan Yinyun. It also absorbed music from other operas and local Zhili musical art forms. Some scholars believe that the Xipi musical form was derived from the historic Qinqiang, while many conventions of staging, performance elements, and aesthetic principles were retained from Kunqu, the form that preceded it as court art.

Thus, Peking opera is not a monolithic form, but rather a coalescence of many older forms. However, the new form also creates its own innovations. The vocal requirements for all of the major roles were greatly reduced for Peking opera. The Chou, in particular, rarely has a singing part in Peking opera, unlike the equivalent role in Kunqu style. The melodies that accompany each play were also simplified, and are played with different traditional instruments than in earlier forms. Perhaps most noticeably, true acrobatic elements were introduced with Peking opera. The form grew in popularity throughout the 19th century. The Anhui troupes reached their peak of excellence in the middle of the century and were invited to perform in the court of the Taiping Heavenly Kingdom that had been established during the Taiping Rebellion. Beginning in 1884, the Empress Dowager Cixi became a regular patron of Peking opera, cementing its status over earlier forms like Kunqu. The popularity of Peking opera has been attributed to the simplicity of the form, with only a few voices and singing patterns. This allowed anyone to sing the arias themselves.

At the time of its growth in the late nineteenth century, albums became used to display aspects of stage culture, including makeup and costumes of performers.