This dissertation is conceived as a theoretical - empirical study, which is focused on modifications in attitudes of fourth and fifth grade pupils towards people with disabilities. The research is based on three possible influences for attitudes, (1) the effect of classmate with disability on pupils' attitudes towards people with disability, (2) teacher's approach to the issue, their inclusive teaching competences and the effect on pupils' attitudes and (3) if school and its inclusive setting (which is represented by schools with "Fair school" certificate) has any influence on pupils' attitudes towards persons with disabilities. We try to explain one elemental empirical question by dealing with these three particular research issues. Does inclusive environment have positive influence on fourth and fifth grade pupils towards people with disabilities? We decided to choose a quasiexperimental design of this study to answer this question. Two validated empirical instruments were used in the research, they were administrated on a sample that consists of 1948 pupils from fourth and fifth grades and (their) 102 teachers. The acquired data were processed by appropriate statistical methods. Our outcomes partly confirmed the assumption that inclusive environment may have an impact on pupils' attitude towards...