Objective To study the role of serum TAP and CRP in occurrence and development of acute pancreatitis(AP) in rats. It can provide a theory basis for early diagnosis of AP. Methods 96 specific pathogen free(SPF) Wistar male rats were divided into two groups randomly (n=48 in each group): sham-operated group and AP model group. In sham-operated group,we only opened the abdominal cavity and touched pancreas several times.In AP model group, 5% Na-Tc was injected under the membrane of pancreas to establish AP animal model. The rats were killed at 3 rd, 6 th, 12 th and 24 th hour after modeling in each group. A portion of pancreatic tissues was examined by hematoxylin-eosin(HE) staining. We detected the concentration of TAP and CRP in serum by enzyme-linked immunosorbent assay(ELISA) . Results The concentration of TAP in sham-operated group, compared with AP group at the same time, was significantly different (P＜0.05). The concentration of TAP in AP group had significant differences (P＜0.05) compared with each other. The concentration of CRP in sham-operated group at 6th, 12th, 24th hour compared with AP group at the same time was significantly different (P＜0.05). The concentration of CRP in AP group had significant differences (P＜0.05) compared with each other. The concentration of TAP and CRP showed higher positive correlation with the pancreatic histopathologic scores. Conclusions Serum TAP can be used for diagnosis of AP in early stage for judgment. TAP and CRP detected dynamically in AP in early stage can be used as indicators of serverity, which plays an important role in forecasting AP.