In Turkey, it is predicted that the need for STEM employment in the 2016-2023 period will be close to one million and that about 31% of this need will not be met. Therefore, the identification of students' interest in STEM careers in middle-school is regarded as important. The aim of this research was to identify the interest of middle-school students in STEM careers. The sample of the research was made up of 892 students who received education in four middle-schools in the Aegean region of Turkey. In this research which was of the descriptive survey model, the STEM Career Interest Questionnaire was used to collect data. As a result of research, it was determined that the interest of male students in STEM careers is more positive compared to the female students. It was found that the interest in careers in terms of grade level did not display any differences in the area of technology, whereas it displayed differences in the areas of science, engineering and mathematics. In addition, it was identified that the interest in STEM careers displayed differences in terms of grade level and that as the grade level increases, the interest in STEM careers decreases.