The purpose of this study is to determine the high school students' cognitive structures related to the concepts of work. The participants of the study were composed of the students enrolled in 11. and 12. class of an Anatolian high school in Turkey. The data were collected via word association test related to the key concept to determine the students' cognitive structures. The collected data were analyzed according to the content analysis method. In the data analysis process, we determined firstly the number of words, the number of answers and the semantic relations between the words written by students. The words having semantic connections were grouped under the same category. Thus, at the end of the study, high school students' cognitive structures and some alternative conceptions were determined related to concepts of work.