Abstract The aim of this thesis was to conduct critical discourse analysis on conversations of Vision 3 textbook based on Fairclough’s three-dimensional model. The purpose of performing the study with critical discourse analysis approach was to investigate the ideological and sociocultural elements and aspects of Vision 3 conversations. Analysis of the contents, topics, themes, speaking characters, situations, contexts and textual characteristics of the conversations revealed that the ideological and cultural aspects and elements of the conversations include predominance of male characters, valuing knowledge and education, honoring national history, culture and famous figures, nationalism, patriotism and encouragement for curiosity. The analysis also showed that the conversations were inauthentic, unrealistic and unnatural. Implications and possible benefits of adapting and integrating critical discourse analysis in teaching English language include revision of the materials and instructional texts, development of supplementary and compensational materials and activities and improvement of critical thinking.