The 1975 Banqiao Dam failure was the collapse of the Banqiao Dam and 61 other dams in Henan, China, under the influence of Typhoon Nina in August 1975. The dam collapse created the third-deadliest flood in history which affected a total population of 10.15 million and inundated around 30 cities and counties of 12,000 square kilometres (or 3 million acres), with an estimated death toll ranging from 26,000 to 240,000. The flood also caused the collapse of 5 million to 6.8 million houses. The dam failure took place when many people were preoccupied with the Cultural Revolution.

Most of the dams that collapsed in this disaster were built with the help of experts from the Soviet Union or during the Chinese Great Leap Forward. The construction of the dams focused heavily on the goal of retaining water and overlooked their capacities to prevent floods, while the quality of the dams was also compromised due to the Great Leap Forward. The Banqiao dam had been designed for a calculated one in a thousand year rainfall event of 300 mm/day; however, more than the normal yearly rainfall (1060 mm) fell in just one day near the typhoon centre. Some experts have also stated that the focus on peasant steel production during the Great Leap Forward, as well as a number of policies from "Learn from Dazhai in agriculture" campaign, severely damaged the ecosystem and forest cover in the region, which was a major cause of the flood, and the government's mishandling of the dam failure contributed to its severity.

The Chinese Communist Party (CCP) as well as the Chinese government subsequently concealed the details of the disaster until the 1990s, when The Great Floods in China's History, a book prefaced by Qian Zhengying who served as the Minister of Water Resources of China in the 1970s and 1980s, revealed details of the disaster to the public for the first time. The official documents of the disaster were declassified in 2005 by the Chinese government.