Map - Sichuan (Sichuan Sheng)

Sichuan (, ; ; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the Sichuan Basin and the easternmost part of the Tibetan Plateau between the Jinsha River on the west, the Daba Mountains in the north and the Yungui Plateau to the south. Sichuan's capital city is Chengdu. The population of Sichuan stands at 83 million. Sichuan neighbors Qinghai to the northwest, Gansu to the north, Shaanxi to the northeast, Chongqing to the east, Guizhou to the southeast, Yunnan to the south, and the Tibet Autonomous Region to the west.

In antiquity, Sichuan was the home of the ancient states of Ba and Shu. Their conquest by Qin strengthened it and paved the way for Qin Shi Huang's unification of China under the Qin dynasty. During the Three Kingdoms era, Liu Bei's state of Shu was based in Sichuan. The area was devastated in the 17th century by Zhang Xianzhong's rebellion and the area's subsequent Manchu conquest, but recovered to become one of China's most productive areas by the 19th century. During World War II, Chongqing served as the temporary capital of the Republic of China, making it the focus of the Japanese bombing. It was one of the last mainland areas captured by the People's Liberation Army during the Chinese Civil War and was divided into four parts from 1949 to 1952, with Chongqing restored two years later. It suffered gravely during the Great Chinese Famine of 1959–61 but remained China's most populous province until Chongqing Municipality was again separated from it in 1997.

The Han Chinese people of Sichuan speak distinctive Sichuanese dialects of Mandarin Chinese. The spicy Sichuan pepper is prominent in modern Sichuan cuisine, featuring dishes—including Kung Pao chicken and mapo tofu—that have become staples of Chinese cuisine around the world. In 1950, the province of Xikang was dissolved and its territory was later split between the newly established Tibet Autonomous Region and the Province of Sichuan. The western and northwestern part of Sichuan is made up of Tibetan and Qiang autonomous areas.

Sichuan is the 6th-largest provincial economy of China, the largest in Western China and the second largest among inland provinces after Henan. As of 2021, its nominal GDP was 5,385 billion yuan (US$847.68 billion), ahead of the GDP of Turkey of 815 billion. Compared to a country, it would be the 18th-largest economy as well as the 19th most populous as of 2021.

There are many panda stations in the province and large reserves for these creatures, such as Chengdu Research Base of Giant Panda.

It is commonly believed that the name Sichuan means "four rivers", and in folk etymology, this is usually taken to mean four of the province's major rivers: the Jialing, Jinsha (or Wu), Min, and Tuo. According to historical geographer Tan Qixiang, "four rivers" is an erroneous interpretation of the place's name. The name of the province is a contraction of the phrases Sì Chuānlù (, "Four Plain Circuits") and Chuānxiá Sìlù (川峡四路, "Four Circuits of Chuanxia"), referring to the division of the existing imperial administrative circuit in the area into four during the Northern Song dynasty, which was Yizhou, Lizhou, Zizhou, and Kuizhou. The word chuan here means "plain", not its normal meaning of "river" as popularly assumed. In addition to its postal map and Wade-Giles forms, the name has also been irregularly romanized as Szű-chuan and Szechuan.

In antiquity, the area of modern Sichuan including the now separated Chongqing Municipality was known to the Chinese as Ba-Shu, in reference to the ancient states of Ba and Shu that once occupied the Sichuan Basin. Shu continued to be used to refer to the Sichuan region all through its history right up to the present day; several states formed in the area used the same name, for example, the Shu of the Three Kingdoms period, and Former Shu and Later Shu of the Ten Kingdoms period. Currently, both the characters for Shu and Chuan are commonly used as abbreviations for Sichuan.