The 12 September 1980 military coup oversaw the discontinuation of the activities and in some cases complete closure of political parties, associations and unions. The military government was not discriminative about the social groups considered to be responsible for the period of social chaos that preceded the September 12 Coup, and arrested, interrogated, tried and sentenced, including death sentences, large groups of people from both the rightist and leftist wings. Mass trials constituted a considerable part of these cases, among which a prominent one was the Peace Association Case. The case was given names such as “the trial of Peace” and “peace convicts” and heavily criticized for its unlawfulness and judging “ideas”. The indictment prepared for this case and the questions asked during the trial as well as the claims and replies of the Association constitute significant examples that provide an understanding of the anti-communist discourse and approach which had been influential in Turkey for a long time. In this regard, this case was also significant for transforming into a medium through which a group of leftists could express themselves. This study which is based on the document analysis method, is original for submitting a special and unexamined example that will facilitate an understanding of the fact that the anti-communist approach, which had been considerably effective as from the start of the Cold War era, and remained unchanged during both the democratic periods and the periods of military government.