Abstract: Objective: To investigate role of serum Proprotein convertase subtilisin/kexin type 9 (PCSK9) level in predicting local complications and clinical prognosis in AP. Methods: 46 acute pancreatitis patients are enrolled in our research according to standard diagnostic criteria, and are stratified as mild, moderately severe and severe following 2012 revised Atlanta classification system. Serum samples are taken at d0, d3, and d10, and PCSK9 level are obtained via ELISA method. Other biochemistry profile and imaging data are collected as well through our hospital’s EMR system. Local complications are determined following CT severity score (the Balthazar score). Serum samples of 40 patients prior to ESD procedures with proven negative results are enrolled as control group. Results:(1) Upon admission, PCSK9 serum level is significantly elevated in AP patient comparing to control group. Following stratified analysis revealed that elevation of PCSK9 level in all MAP, MSAP and SAP groups are statistically significant when comparing to ctrl group. (2) Logistic regression revealed that PCSK9 serum level at d0 and ALT level are isolated risk factor/protective factor to local complication in acute pancreatitis. (3) Logistic regression revealed that sufficient decrease of serum PCSK9 level is isolated protective factor to adverse clinical outcome in its clinical course. (4) Spearman’s correlation revealed that elevation of PCSK9 level is dispensable to lipid elevation in acute pancreatitis. Conclusion: PCSK9 can be utilized as a novel predictive marker for local complications and prognosis in acute pancreatitis.