Osman Bölükbaşı is one of the most eminent political actors that comes to mind due to his dissenting stance in Turkey's political life. He started politics in the Democratic Party during the transition to multiparty life and founded his own independent movement against the ruling Republican People's Party and the DP, whose opposition he deemed inadequate. The aim of the article is to shed light on Bölükbaşı's views on the May 27 coup and the March 12 memorandum, and his opposition between these two terms. In this context, the article focuses on the struggle of the movement initiated by Bölükbaşı against the suppressive attempts of the CHP, DP, the 27 May junta and the Justice Party. In the first part, the personal and political life of Bölükbaşı is reviewed. In the following sections, the style of the political opposition that Bölükbaşı had adopted was examined in various phases, namely before, during and after the DP's rule, especially the period from 27 May to 12 March. In this qualitative research based on the doctoral thesis, primary source memories and books were used, as well as the archives of the Parliament and newspapers of the period.