The Yangtze or Yangzi (English: or ; simplified Chinese: ; traditional Chinese: ; pinyin: Chng Jing; lit. 'long river') is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows 6,300 km (3,900 mi) in a generally easterly direction to the East China Sea. It is the seventh-largest river by discharge volume in the world. Its drainage basin comprises one-fifth of the land area of China, and is home to nearly one-third of the country's population.The Yangtze has played a major role in the history, culture, and economy of China. For thousands of years, the river has been used for water, irrigation, sanitation, transportation, industry, boundary-marking, and war. The prosperous Yangtze Delta generates as much as 20% of China's GDP. The Three Gorges Dam on the Yangtze is the largest hydro-electric power station in the world that is in use. In mid-2014, the Chinese government announced it was building a multi-tier transport network, comprising railways, roads and airports, to create a new economic belt alongside the river.The Yangtze flows through a wide array of ecosystems and is habitat to several endemic and threatened species including the Chinese alligator, the narrow-ridged finless porpoise, and also was the home of the now extinct Yangtze river dolphin (or baiji) and Chinese paddlefish, as well as the Yangtze sturgeon, which is extinct in the wild. In recent years, the river has suffered from industrial pollution, plastic pollution, agricultural runoff, siltation, and loss of wetland and lakes, which exacerbates seasonal flooding. Some sections of the river are now protected as nature reserves. A stretch of the upstream Yangtze flowing through deep gorges in western Yunnan is part of the Three Parallel Rivers of Yunnan Protected Areas, a UNESCO World Heritage Site.

The Three Gorges Dam is a hydroelectric gravity dam that spans the Yangtze River by the town of Sandouping, in Yiling District, Yichang, Hubei province, central China, downstream of the Three Gorges. The Three Gorges Dam has been the world's largest power station in terms of installed capacity (22,500 MW) since 2012. The dam generates an average 95±20 TWh of electricity per year, depending on annual amount of precipitation in the river basin. After the extensive monsoon rainfalls of 2020, the dam's annual production nearly reached 112 TWh, breaking the previous world record of ~103 TWh set by Itaipu Dam in 2016.The dam body was completed in 2006. The power plant of the dam project was completed and fully functional as of July 4, 2012, when the last of the main water turbines in the underground plant began production. Each main water turbine has a capacity of 700 MW. Coupling the dam's 32 main turbines with two smaller generators (50 MW each) to power the plant itself, the total electric generating capacity of the dam is 22,500 MW. The last major component of the project, the ship lift, was completed in December 2015.As well as producing electricity, the dam is intended to increase the Yangtze River's shipping capacity. By providing flood storage space, the dam reduces the potential for floods downstream which have historically plagued the Yangtze Plain. In 1931, floods on the river caused the deaths of up to 4 million people. As a result, China regards the project as a monumental social and economical success, with the design of state-of-the-art large turbines, and a move toward limiting greenhouse gas emissions. However, the dam has caused ecological changes including an increased risk of landslides. Because of that, the dam has been controversial both domestically and abroad.