This study investigates the engineering epistemological beliefs (EEB) of Turkish vocational high school students. The goal of this research is to reveal changes in these beliefs across grade levels, discipline, and gender. The present study included 314 vocational high school students from five schools in two Turkish cities. A Turkish version of the epistemological belief assessment for engineering (EBAE) questionnaire was created and used to assess student EEBs. Descriptive results indicated that as grade increased, average scores of students' EEB decreased with respect to almost all dimensions of the EBAE. Males reported more sophisticated beliefs than females for all EEB dimensions except for justification for engineering knowing. Participants studying the metal technology discipline reported the most naive EEB, while those studying information technologies displayed the most sophisticated beliefs. The results of inferential statistics showed that while the effect of gender, discipline and grade level were not significant with students' EEB, the effect of interaction of grade level and discipline on students' EEB was statistically significant. This study implies that the vocational school curricula in Turkey should be reconsidered in terms of student engineering epistemological growth.