The Imperial Rule Assistance Association (Japanese: 大政翼贊會/大政翼賛会, Hepburn: Taisei Yokusankai), or Imperial Aid Association, was the Empire of Japan's ruling political organization during much of the Second Sino-Japanese War and World War II. It was created by Prime Minister Fumimaro Konoe on 12 October 1940, to promote the goals of his Shintaisei ("New Order") movement. It evolved into a statist, para-fascist ruling political party which aimed at removing sectionalism and factionalism from politics and economics in the Empire of Japan, creating a totalitarian one-party state in order to maximize the efficiency of Japan's total war effort against China and later the Allies. When the organization was launched officially, Konoe was hailed as a "political savior" of a nation in chaos; however, internal divisions soon appeared.

Based on recommendations by the Shōwa Kenkyūkai (Shōwa Research Association), Konoe originally conceived of the Imperial Rule Assistance Association as a reformist political party to overcome the deep-rooted differences and political cliques between bureaucrats, politicians and the military. During the summer of 1937, Konoe appointed 37 members chosen from a broad political spectrum to a preparatory committee which met in Karuizawa, Nagano. The committee included Konoe's political colleagues Fumio Gotō, Count Yoriyasu Arima and entrepreneur and right-wing spokesman Fusanosuke Kuhara. A radical wing of the military was represented by Kingoro Hashimoto, while the traditionalist military wings were represented by Senjūrō Hayashi, Heisuke Yanagawa and Nobuyuki Abe.

Konoe proposed originally that the Imperial Rule Assistance Association be organized along national syndicalist lines, with new members assigned to branches based on occupation, which would then develop channels for mass participation of the common population to "assist with the Imperial Rule".

However, from the start, there was no consensus in a common cause, as the leadership council represented all ends of the political spectrum, and in the end, the party was organized along geographic lines, following the existing political sub-divisions. Therefore, all local government leaders at each level of village, town, city and prefectural government automatically received the equivalent position within their local Imperial Rule Assistance Association branch.

Prior to creation of the Imperial Rule Assistance Association, Konoe had already passed the National Mobilization Law, which effectively nationalized strategic industries, the news media, and labor unions, in preparation for total war with China.

Labor unions were replaced by the Nation Service Draft Ordinance, which empowered the government to draft civilian workers into critical war industries. Society was mobilized and indoctrinated through the National Spiritual Mobilization Movement, which organized patriotic events and mass rallies, and promoted slogans such as "Yamato-damashii" (Japanese spirit) and "Hakkō ichiu" (All the world under one roof) to support Japanese militarism. This was urged to "restore the spirit and virtues of old Japan".

Some objections to it came on the grounds that kokutai, imperial polity, already required all imperial subjects to support imperial rule.

In addition to drumming up support for the ongoing wars in China and in the Pacific, the Imperial Rule Assistance Association helped maintain public order and provided certain public services via the tonarigumi neighborhood association program. It also played a role in increasing productivity, monitoring rationing, and organizing civil defense.