Objective: Occupational diseases originated from workplace environment during the profession are all preventable diseases. Every year, approximately 160 million people get occupational diseases around the world. As a result, awareness of employees about occupational diseases is important and necessary. Aim of this study is to determine the level of knowledge of occupational diseases in Technical Vocational School students. Methods: The descriptive cross-sectional study consisted of 207 students studying at the Vocational School, and it was aimed to reach the entire universe. The study was conducted between October-November 2016 and reached 163 (78.7%). A 26-question questionnaire was applied. The data were evaluated in SPSS 19.0 Results: 131 of the students were male (80.4%) and the average age was 19.86 ± 3.69. The knowledge level of 83.4% (136 people) of the students was insufficient. There was no significant difference between the level of knowledge and gender, graduated secondary education and departments. According to the correct answers averages of the knowledge level measurement questions, the most correct answer was 133 persons (81.6%) and the definition of occupational diseases,the least correctly answered question is 10 persons (6.1%) and the most effective protection from occupational diseases. Conclusions: This study reveals that, the level of knowledge about the occupational diseases of our students may be inadequate. According to the results obtained, awareness of the students about occupational infections, occupational diseases due to biological factors and methods of protection from occupational diseases is at the lowest level. Organisation of conferences and panels about these subjects also extra courses about occupational diseases is suggested to the school management. Keywords: awareness, occupational diseases, vocational school students