Sichuanese Mandarin (simplified Chinese: 四川官话; traditional Chinese: 四川官話; pinyin: Sìchuān Guānhuà), or Szechwanese Mandarin, commonly known as Sichuanese, Szechuanese or Szechwanese (simplified Chinese: 四川话; traditional Chinese: 四川話; Sichuanese Pinyin: Si4cuan1hua4; pinyin: Sìchuānhuà; Wade–Giles: Szŭ4-ch'uan1-hua4), is a branch of Southwestern Mandarin, spoken mainly in Sichuan and Chongqing, which was part of Sichuan until 1997, and the adjacent regions of their neighboring provinces, such as Hubei, Guizhou, Yunnan, Hunan and Shaanxi. In addition, because Sichuanese is the lingua franca in Sichuan, Chongqing and part of Tibet, it is also used by many Tibetan, Yi, Qiang and other groups as a second language.
Although Sichuanese is generally classified as a dialect of Mandarin, it is highly divergent in phonology, vocabulary, and even grammar from the standard language.Minjiang dialect is especially difficult for speakers of other Mandarin dialects to understand. The dialect of Chengdu, the capital of Sichuan province and an important central city, is the most representative dialect of Southwestern Mandarin and is used widely in Sichuanese opera and other art forms of the province.