The fundamental purpose of the function of thinking is to attribute meaning to events in our lives, classify these events into categories and identify them subjectively. As an important dimension of education on thinking, the teaching of critical thinking since the 1950s has attained a wide conceptual framework. Accepted as a factor that facilitates the aquisition and comprehension of information, critical thinking is a desirable learning outcome of education. Some of the characteristics and properties of critical thinking are being aware, systematic, flexible and patient, encompassing open-meaning, metacognition, reconstruction, motivation and discussion. From this point, the perceptions of the students of Karabuk University, English Language and Literature Department, regarding critical thinking, were investigated in detail, in the Spring semester of the academic year 2017-2018. This study is a descriptive one and utilises the survey model to determine the levels of critical thinking in 222 teacher candidates, comprised of students ranging from freshmen to seniors and from both daytime and evening education. The findings have been evaluated and a set of conclusions have been drawn. While a statistical difference according to classes was not found when Anova results were analysed on the sub-dimensions of metacognition, flexibility, systematicity, open-mindedness, a difference was found between the sophomore and senior students on the sub-dimension of perseverance-patience.