The outbreak of the coronavirus disease 2019 (Covid-19) shows a global spreading trend. Early and effective predictors of clinical outcomes is urgent needed to improve management of Covid-19 patients.The aim of the present study was to evaluate whether elevated D-dimer levels could predict mortality in patients with Covid-19.Patients with laboratory confirmed Covid-19 were retrospective enrolled in Wuhan Asia General Hospital from January 12, 2020 to March 15, 2020. D-dimer levels on admission, and death events were collected to calculate the optimum cutoff using receiver operating characteristic curve. According to the cutoff, the subjects were divided into two groups. Then the in-hospital mortality between two groups were compared to assess the predictive value of D-dimer level.A total of 343 eligible patients were enrolled in the study. The optimum cutoff value of D-dimer to predict in-hospital mortality was 2.0 µg/ml with a sensitivity of 92.3% and a specificity of 83.3%. There were 67 patients with D-dimer≥2.0 µg/ml, and 267 patients with D-dimer <2.0 µg/ml on admission. 13 deaths occurred during hospitalization. Patients with D-dimer levels≥2.0 µg/ml had a higher incidence of mortality when comparing to those who with D-dimer levels < 2.0 µg/ml (12/67 vs 1/267, P<0.001, HR:51.5, 95%CI:12.9-206.7).D-dimer on admission greater than 2.0µg/mL (fourfold increase) could effectively predict in-hospital mortality in patients with Covid-19, which indicated D-dimer could be an early and helpful marker to improve management of Covid-19 patients.