Background and aimsTo specify the prevalence of patients diagnosed with CF at age of ≥60 year-old and to analyze their characteristics.Patients and methodsObservational study of CF patients which were diagnosed at age ≥60 year-old. The analyzed variables were: age, sex, nationality, lung function parameters, conditions present at diagnosis, microbiological characteristics and genetic findings.Resultseight patients were included. 7 patients were female (87.5%) with a mean age of 70.6 years (median 71.5 years, range 60–78 years). The most important findings were: sweat test >60 mEq/l; heterozygotes F508del; bronchiectasis in CT; methicillin-sensitive Staphylococcus aureus (50%) in sputum. The most patients presented a normal or mild obstructive lung function.ConclusionsCF must also be considered a disease diagnosed in adulthood, incorporating the sweat test within the usual techniques of differential diagnosis in patients with different diseases associated with CF, because genetic counselling is esencial.