Adults have a key role in ensuring that society is democratic and sustainable, by making decisions about the permanence and continuity of the world/society, and as role models to the new participants in a democratic society. In this context, the purpose of this research is to determine the citizenship education needs of adults in a sustainable democratic society. The study was designed in a qualitative research pattern and was carried out using the case study method. The study group consisted of adults, who were determined by criteria sampling method. Demographic data, a semi-structured interview form, and scenario texts were used to obtain data. The data obtained were analysed by using the content analysis method. Perspectives on adult citizenship education were presented according to the themes created. It was found that participants have a citizenship tendency in line with the traditional national citizenship approach and behaved accordingly. In conclusion, this study proposes that citizenship education should be organized for adults, who are today’s decision makers and role models for tomorrow’s decision makers, in order to improve their political literacy, legal literacy, and political, social, civic engagement and democratic values, which will contribute to the goal of a sustainable democracy in society.