Pain is a potential complication of cystic fibrosis (CF), but its consequences in daily life and other issues of pain management are not yet clearly understood. We undertook a comparative study of children and adults with CF to assess the prevalence of pain symptoms, their characteristics and treatment, their impact on daily quality of life, and the occurrence of procedural pain. The study included 73 children (1-18 years) and 110 adults (18-52 years); 59% of the children and 89% of the adults reported at least one episode of pain during the previous month. Pain was significantly more intense and lasted significantly longer among adults, but its rate and recurrence did not differ significantly between the two populations and were not related to the severity of CF. The most prevalent locations were the abdomen for children, and the back, head, and chest for adults. Although pain significantly limited physical activity, only 15% of patients reported that it caused absenteeism, and 27% reported that it negatively affected their family life. The mean pain intensity rates on a visual analog scale for the episode that had caused the greatest pain during the past month were 4.9 (2) (mean [SD]) for children and 6 (2) for adults; however, only 40% and 50%, respectively, of those with pain reported the use of analgesic treatment, mainly paracetamol (acetaminophen). At least one episode of procedural pain during the previous month was reported by 85% of children and 78% of adults. Our study demonstrates the high incidence of undertreated pain in CF patients throughout their lives.