Objective ·To explore the diagnostic and treatment methods for patients with cystic fibrosis (CF) complicated by allergic bronchopulmonary aspergillosis (ABPA), and to enhance clinicians' understanding of these two diseases. Methods ·A retrospectively analysis was conducted on the clinical data of 5 patients with CF complicated by ABPA admitted to the Department of Respiratory Medicine, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, from July 2023 to August 2024. A literature search was performed in PubMed, Web of Science, Cochrane Library, and CNKI for studies published in the past 10 years regarding the co-existence of these diseases. Clinical manifestations, treatment courses, and current epidemiological research were summarized and analyzed. Results ·Common symptoms of patients with CF complicated by ABPA included aggravated cough and expectoration, wheezing, fever, and dyspnea. Whole-exome aequencing indicated mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, and an increase in the concentration of chloride ions in sweat. The levels of total serum immunoglobulin E (IgE) and Aspergillus fumigatus-specific IgE increased, and chest computed tomography (CT) showed bronchiectasis and mucus plugging. CF complicated by ABPA is often missed or misdiagnosed for asthma. In China, ABPA is often diagnosed before CF, whereas in Caucasian populations CF is typically diagnosed first. Initial treatment usually involves long-term oral administration of antifungal drugs such as voriconazole combined with glucocorticoids such as prednisone. For patients with frequent relapses or severe side effects, alternative antifungal agents or omalizumab therapy may be considered. Co-infection with Pseudomonas aeruginosa is common, often requiring intravenous antibiotics such as cefoperazone-sulbactam. Current epidemiological research focuses mainly on clinical characteristics, treatment regimens, and novel diagnostic methods. Conclusion ·ABPA and CF have overlapping symptoms. Accurate diagnosis of CF complicated by ABPA requires genetic testing, sweat chloride measurement, chest CT, and serological tests. The coexistence of these diseases often leads to missed, delayed, or incorrect diagnosis, increasing patient burden. Present epidemiological studies mainly address clinical characteristics with a lack of targeted clinical drug trials for this patient population.