Objective: To investigate the significance of serum C-reactive protein (CRP), procalcitonin (PCT) and lipase levels in predicting infectious pancreatic necrosis in patients with severe acute pancreatitis (SAP). Methods: A total of 224 patients with SAP) were enrolled from September 2018 to September 2017. There were 78 patients in the infection group and 146 patients in the non-infected group. All patients received comprehensive medical treatments such as fasting and gastrointestinal decompression. Venous blood was taken on day 1 and day 7 for determination of serum CRP, PCT and blood lipase levels, and other indicators such as white blood cell count, hemoglobin (Hb), albumin (Alb) and blood amylase (AMS). At the same time, 150 healthy subjects were used as the control group. Serum CRP, PCT and lipase levels were compared amongst the three groups. Results: Serum CRP, PCT and lipase levels in healthy subjects were 2.61 +/- 0.74 mg/L, 0.05 +/- 0.01 ng/ml and 180.26 +/- 54.47 U/L, respectively. In patients with severe acute pancreatitis, serum CRP, PCT and lipase levels were 53.67 +/- 9.91 mg/L, 4.68 +/- 0.97 ng/ml and 463.78 +/- 121.43 U/L, respectively on the first day, and 178.54 +/- 49.26 mg/L, 11.28 +/- 3.36 ng/ml and 662.49 +/- 157.81 U/L, respectively on the 7th day. The indicators were significantly different between the severe acute pancreatitis group and the control group (p < 0.05). Serum CRP, PCT and lipase in the infected group were higher than those in the non-infected group on day 1 and day 7 (p < 0.001). The white blood cell count, hemoglobin, albumin and blood amylase were 14.32 +/- 4.57 x109/L, 108.21 +/- 10.06 g/L, 35.03 +/- 4.82 g/L, and 706.84 +/- 168.31 U/L, respectively. There were no significant differences between the non-infected group and the infected group. Conclusion: The levels of serum CRP, PCT and blood lipase are significantly elevated in patients with SAP, and they of predictive values for infectious pancreatic necrosis in these patients.