Solidarity union may refer to:

Trade unions Solidarity unionism, a model of labor union organizing Solidarity Union, a trade union in New Zealand Solidarity (British trade union), a trade union in the United Kingdom Solidarity (Polish trade union), a trade union in Poland Solidarity (South African trade union), a trade union in South Africa

Other Taiwan Solidarity Party, a political party in Taiwan formerly known as the Taiwan Solidarity Union Non-Partisan Solidarity Union, a political party in Taiwan