Objective: To determine the value of plasma D-dimer level for predicting in-hospital death in patients with acute aortic dissection (AD). Methods: The clinical data of 83 AD patients admitted from January 2013 to December 2015 were collected. The patients were divided into survival group (62 cases) and mortality group (21 cases) according to whether or not they died during hospitalization, and the D-dimer levels and other related clinical variables of the two groups were compared, and the risk factors for in-hospital death of the patients were determined by regression analysis. Results: There were no difference in factors that included age, gender, smoking, hypertension and diabetes between the two groups (all P>0.05), while the proportion of patients with type A disease and D-dimer level were significantly increased in mortality group compared with survival group (both P<0.05). Logistic regression analysis showed that type A disease (OR=0.117, 95% CI=0.021–0.792) and D-dimer level (OR=3.180, 95% CI=1.551–5.984) were risk factors for in-hospital death of the patients (both P<0.05). The area under the receiver operating characteristic curve for D-dimer level predicting death was 0.819 (95% CI=0.807–0.974, P<0.001), with cut-off value of 4.85 μg/mL, and sensibility and specificity of 85.7% and 75.8%, respectively. Conclusion: D-dimer level, as a rapid detecting index, can be used for simple risk assessment of AD patients and aggressive interventions should be made for those with high D-dimer level.