Abstract： Objective To evaluate the characteristics of the CT perfusion for severe acute pancreatitis. Methods We performed CT perfusion scan on three groups of 9, 17and 41 cases with severe,mild and normal pancreatitis respectively, using 16 rows spiral CT, and got the perfusion data of the relevant groups including blood flow (BL), blood volume(BV), mean transit time( MTT), capillary permeability(PS)with perfusion package 3. We analize the data deviation between the groups mentioned above. Furthmore, we still adapt correlation test to compare the clinical biochemical indicators of MAP and SAP, with the variance BF. Results The mean values of BF, BV reduce significally in the groups of MAP, SAP compared to thenormal group(P＜0.01 ), only PS goes higher than that of the normal group(P＜0.05). At the same time,they are obviously higher in MAP group than in SAP group. In MAP group, the level of blood hemodiastase and BF are negatively correlated, on the contray, in SAP group, the level of the blood hemodiastase has no relation to BF. Conclusions CT perfusion techniques are of great significance in early diagnosis in SAP, and in guiding the clinical therapy.