Background: Several predictors for the severity of coronavirus disease MESHD 2019 (COVID-19) have been reported, including decreased circulating lymphocytes and eosinophil counts. However, chronic airway inflammation MESHD characterized by accumulated lymphocytes or eosinophils may affect the pathogenesis of COVID-19. We aimed to investigate the predictors for the severity of COVID-19 in patients with chronic airway diseases MESHD.Methods: In this retrospective cohort study, we reviewed medical records of all laboratory-confirmed COVID-19 patients with chronic bronchitis MESHD chronic bronchitis HP, chronic obstructive pulmonary disease MESHD chronic obstructive pulmonary disease HP (COPD) and asthma MESHD asthma HP admitted in Sino-French New City Branch of Tongji Hospital, a large regional hospital in Wuhan, China, from January 26th to April 3rd. The Tongji Hospital ethics committee approved this study.Results: There were 59 patients with underlying chronic airway inflammation MESHD including chronic bronchitis MESHD chronic bronchitis HP, COPD, and asthma MESHD asthma HP. When compared with non-severe patients, severe patients were more likely to have decreased lymphocyte counts (0.6 vs. 1.1× 10⁹/L, p < 0.001), eosinopenia (< 0.02 × 10⁹/L, 73% vs. 24%, p < 0.001), increased lactate dehydrogenase (LDH) (471.0 vs. 230.0 U/L, p < 0.001) and elevated IL-6 level (47.4 vs. 5.7 pg/ml, p = 0.002) on admission. Eosinopenia and elevated LDH were significantly associated with disease MESHD severity in both univariate and multivariate regression models included the above variables. Eosinopenia was also an independent risk factor for mortality of this cohort in a multivariate model included the above variables. Moreover, eosinophil counts and LDH levels tended to return to normal range over time in both groups after treatment and severe patients recovered slower than non-severe patients, especially eosinophil counts.Conclusions: Eosinopenia and elevated LDH are potential predictors of disease MESHD severity in COVID-19 patients with underlying chronic airway diseases MESHD. Theses predictors may help clinicians identify the severe COVID-19 patients with chronic bronchitis MESHD chronic bronchitis HP, COPD, and asthma MESHD asthma HP.