This study aims at investigating social studies student teachers' levels of understanding sociology concepts within social studies curriculum. Study group of the research consists of 266 teacher candidates attending the Department of Social Studies, Faculty of Education, Kastamonu University during 2012 to 2013 education year. A semi-structured concept scale consisting of 12 questions has been used with the student teachers. Student teachers' responses have been content-analyzed on categories of "understanding", "limited understanding", "not understanding", "being unable to respond", and "misunderstanding (misconception)". Analysis showed that social studies student teachers often express sociology concepts within social studies curriculum on the levels of "limited understanding" and "not understanding". Student teachers' the most encountered misconceptions among sociology concepts are "socialization" and "social institution". (Contains 1 table.)