Abstract： Objective:To analyze the clinical characteristics and short-term prognosis of patients with acute asthmatic attack and comorbid bronchiectasis.Methods:The data of patients hospitalized for acute asthmatic attack in the Department of Respiratory and Critical Care Medicine of Peking University Third Hospital from January 1, 2012 to December 31, 2021 were retrospectively collected and analyzed. According to whether or not co-existing with bronchiectasis, all the patients were divided into asthmatic with bronchiectasis group and asthmatic without bronchiectasis group. Then the general conditions, comorbidities, pulmonary function test, grades of asthma severity, laboratory examination and in-hospital short-term prognosis of two groups were analyzed.Results:A total of 580 hospitalized patients with acute asthma attack were included, of which 132 cases (22.76%) were classified into asthmatic with bronchiectasis group and 448 cases (77.24%) were classified into asthmatic without bronchiectasis group. Co-existing with obsolete pulmonary tuberculosis and anxiety/depression in asthmatic with bronchiectasis group were more common than that in asthmatic without bronchiectasis group (13.64% vs 5.36%; 7.58% vs 2.68%) (both P<0.05). The pre-bronchodilator forced vital capacity (FVC) and its percentage to the predicted value (FVC%pred), forced expiratory volume in 1 second (FEV 1) and its percentage to the predicted value (FEV 1%pred), FEV 1/FVC and post-bronchodilator FEV 1 in asthmatic with bronchiectasis group were lower than those in the asthmatic without bronchiectasis group [2.44 (1.90, 3.01) vs 2.69 (2.10, 3.68) L, 1.55 (1.13, 2.00) vs 1.78 (1.25, 2.52) L, 70.14% (67.39%, 85.92%) vs 79.63% (70.00%, 89.52%), 70.00% (54.38%, 78.11%) vs 70.00% (61.47%, 85.00%), 61.57% (56.29%, 73.03%) vs 66.67% (60.00%, 75.00%), 1.72 (1.21, 2.18) vs 1.89 (1.37, 2.55) L] (all P<0.05). In previous year, the proportion of patients receiving hospitalization due to acute asthmatic attack in asthmatic with bronchiectasis group was higher than that in asthmatic without bronchiectasis group (15.15% vs 8.93%) ( P<0.05). The peak months of hospitalization due to acute asthmatic attack in asthmatic with bronchiectasis group were April, July and October, and the peak months in asthmatic without bronchiectasis group were April and September. The length of hospital stay was longer and the proportion of patients receiving invasive ventilation was higher in asthmatic with bronchiectasis group than those in asthmatic without bronchiectasis group [10.06 (7.62, 13.94) vs 9.95 (7.15, 13.76) d; 5.30% vs 2.01%] (both P<0.05). The risk factors for invasive mechanical ventilation in asthmatic patients with acute attack during hospitalization were co-existing with bronchiectasis, smoking, high level of partial pressure of carbon dioxide in arterial blood, serum creatinine and creatine kinase. Conclusion:Asthma patients with comorbid bronchiectasis have more frequent acute attack, a longer hospitalization due to acute asthmatic attack and a higher probability of invasive ventilation during hospitalization.