This paper reports a novel Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene variant, 1811+1G-->T, detected in a 5-year-old girl diagnosed with idiopathic disseminated bronchiectasis and negative sweat chloride test (17 mmol/L). The performed CFTR gene mutation analysis included detection of the F508del mutation, analysis of Tn polymorphism and screening of CFTR exons 3, 10 and 11. The CFTR gene screening has shown the altered band pattern in exon 11. The DNA sequencing of CFTR exon 11 revealed the presence of the novel sequence variation 1811+1G-->T in heterozygous state. This sequence variation was not found in any of 100 control alleles, analyzed by polymerase chain reaction - restriction fragment length polymorphism method. The novel sequence variation 1811+1G-->T is located at the splicing site at the boundary of exon 11 and intron 11 and might be either a sequence variation or a splicing site defect.