Objective To investigate the value of mean platelet volume(MPV)combined with red blood cell distribution width(RDW)in prognosis of severe acute pancreatitis(SAP). Methods 65 SAP patients from January 1,2013 to December 31,2016 were included in the study and were divided into pospital death group(n=7) and survival group(n = 58). The basic clinical data of two groups were compared,the risk factors for hospital death and the prognostic value of MPV and RDW were analyzed. Results Compared with the survival group,the APACHEⅡ score,RDW,PLT,MPV,PDW were statistically different(P < 0.05). Logistic regression analysis was used to show APACHEⅡ score(OR = 1.793,95% CI: 1.212 ~ 2.654),PLT(OR = 0.982,95% CI: 0.967 ~0.997),MPV(OR=2.964,95% CI: 1.341~6.549),PDW(OR=1.470,95% CI: 1.019~2.122),RDW(OR=3.274,95% CI: 1.271 ~ 8.429)(P < 0.05). ROC curve analysis showed that the area under the curve of APA-CHEII score was 0.861(95% CI: 0.743 ~ 0.979,P = 0.001),MPV was 0.828(95% CI: 0.689 ~ 0.967,P =0.003,RDW was 0.849(95% CI: 0.749 ~ 0.949,P = 0.001),MPV+RDW was 0.914(95% CI: 0.832 ~ 0.997, P = 0.000). Conclusion The APACHEⅡ score,PLT,MPV,PDW,RDW are all the independent risk factors for hospital death with SAP. MPV combined with RDW has an important reference value for the prognosis of SAP patients.