The diploma thesis deals with the issue of mainstream teachers' attitudes towards inclusion of pupils with special educational needs. The objective of the diploma thesis is to identify the mainstream teachers' attitudes towards inclusion of pupils with disabilities. The partial objective is to determine the factors affecting the formation of these attitudes. The analysis of scientific literature and other relevant resources and the questionnaire survey have been utilized to achieve the objective of the thesis. The methods of descriptive statistics and the analysis of variance have been used to process the data gained. The diploma thesis is divided into four chapters. The first chapter concerns the disability classification and categorization and the concepts of integrative and inclusive education. The second chapter focuses on the individual levels of implementation of inclusive education. The third chapter is concerned with the importance of the role of the teacher in the process of inclusion. The final chapter contains the survey in the form of questionnaire, which is related to teachers' sentiments, attitudes and concerns about inclusive education.