CFTR protein (cystic fibrosis trans membrane conductance regulator) is expressed in multiple epithelial tissues, including upper and lower respiratory tracts, pancreas, sweat glands and gastrointestinal tract. More than 800 mutations and 100 polymorphic variants of DNA sequences were identified in patients with CF (Cystic fibrosis) and CFTR-diseases. In this study, genetic CFTR analysis of the children suffering from chronic lung disease (cystic fibrosis) is presented. They are treated and regularly controlled at the Pediatric hospital Sarajevo. CFTR analysis was done in 9 cases, 4 boys (44.4%) and 5 girls (55.55%). There are 3 children (33.3%) in the age group 1 to 3 years, 1 child (11.1%) in the age group 3 to 6 years, 3 children (33.3%) in the age group 6 to 9 years and 2 children (22.2%) in the age group 9 to 12 years. Genetic analysis was conducted at the Medical center for molecular biology, School of Medicine, Ljubljana. PCR method with PAGE and direct sequestration on ABI PRISM 31 was applied. The majority of children (7 children, i.e. 77.77%) had CFTR mutation Delta F 508 whilst one child had G542X mutation and one child R 1174 mutation. The purpose of this study is to emphasize the need for CFTR gene identification in the institutes of our country.