【Abstract】Objectives To assess the viability of using white blood cell counts (WBCc) as a prognostic measure for patients with Stanford type B acute aortic dissection (AAD) after endovascular therapy (EVT). Methods The clinical data were collected from postEVT Stanford type B AAD diagnosed in the West China Hospital of Sichuan University from January 2012 to December. The patients were divided into high WBCc group（＞10×109/L）(72 cases ) and low WBCc group（≤10×109/L）(59 cases) based on their white blood cell counts levels on admission. Collected information included patient basic clinical data, blood test results, major adverse cardiovascular events and survival status during in patient and out-patient follow-ups. The primary end points were death events during in-patient and out-patient follow-ups. The relationship between WBCc and mortality of patients with type B AAD was assessed by Kaplan-Meier survival analysis and COX regression analysis. Results The study enrolled 131 patients, including 97 male (74%). The in-patient's mortality was 9.9% and the out-patient's mortality was 16% after median follow-up time of 2.1 years. KaplanMeier survival curve analysis of the high WBCc (＞10×109/L) group survival rate was significantly lower than the low WBCc(≤10 × 109 / L)（76.4% vs 93.2%, P=0.007）. The high WBCc on admission was identified as an independent risk factor for mortality with type B AAD undergoing EVT by multivariate COX regression analysis（HR：3.667, 95% CI：1.206-11.145, P=0.022）.Conclusion The white blood cell counts may be used a prognosis factor of mortality of patients with type B AAD undergoing EVT.