Japan's second largest labour union federation until it disbanded in 1987.

Dōmei was formed in 1964 by a merger of three politically moderate federations that opposed the leftist stance of the larger and more militant union Sōhyō. Unlike the majority of Sōhyō members, who were public employees, most Dōmei members worked for private-sector firms. Dōmei was a supporter of the Democratic Socialist Party and was affiliated with the International Confederation of Free Trade Unions. It disbanded in 1987 when many of its member unions joined with other private-sector unions to form a new confederation called Rengō the same year. A moderate union, Rengō became Japan's centre of organized labour. Unlike Dōmei, Rengō focused on organizing study groups and forums on labour issues, involving scholars and experts from outside the labour movement. In 1992 Rengō changed its name to Denki Rengō.