Backgound and Aims: It has been reported that acute exacerbation(AE) is one of the leading causes of death in patients with Idiopathic pulmonary fibrosis(IPF). However, clinical characteristics of IPF patients with AE have not yet been fully clarified. The present study was perfomed to find out more elucidated risk factors in IPF AE patients. Methods: From January 2016 to December 2018, a single center retrospective cohort study was performed in all IPF patients who were hospitalized withAE events and other problems at Uijeongbu St. Mary’s Hospital. Clinical characteristics, radiologic features, and laboratory findings between IPF patients with and wituout AE were reviewed and compared. Results: The total study population consisted of 124 patients; 52 (41.9%) were in the AE group and 72 (58.1%) were in the non-AE group. Body mass index (21.76 ± 0.464 vs. 23.54 ± 0.521, p=0.017), baseline forced vital capacity (62.94 ± 15.098 vs. 77.17 ± 20.032, P=0.000), and never smoker proportion (38.5% vs. 61.1%, p=0.013) were significantly lower in the AE group than non-AE group. Anti-platelet and statin medication history (42.3% vs. 16.7%, p=0.002), underlying hypertension (73.1% vs. 47.2%, p=0.004), in case of accompanied pneumonia (57.7% vs. 33.3%, p=0.007), positivie sputum culture (66.7% vs. 25.0%, p=0.000) were significantly higher in the AE group. In radiologic features, lymphadenopathy (65.4% vs. 27.8%, p=0.000), pleural effusion (46.2% vs. 16.7%, p=0.000), and tuberculosis destroyed lung (15.4% vs. 2.8%, p=0.017) were significantly higher in the AE group than non-AE group. In blood test findings, white blood cells (12992.31 ± 828.728 vs. 10067.78 ± 582.469, p=0.004), segment of eosinophils (5.340 ± 1.9024 vs. 1.561 ± 0.2952, p=0.059) were significantly higher in the AE group. There was no significant risk factor in multivariate analysis. Conclusions: A large-scale prospective clinical study should be needed to find more specific risk factors in AE patient.