Objective To investigate the relationship between C-reactive protein and clinical significance of Tokyo Guidelines for acute cholangitis.Methods Analyzed 739 cases with acute cholecystitis in Xianyang Central Hospital of Shaanxi province.Records of patients diagnosed with acute cholecystitis were screened between September 2013 and October 2015.The criteria of Tokyo guidelines were used in grading the severity of acute cholecystitis.Patients were divided into 3 groups,Group Ⅰ (n =450),Group Ⅱ (n =260) and Group Ⅲ (n =29).C-reactive protein values at the time of admission were analyzed and compared among the groups.Results Mean C-reactive protein levels of groups were found to be significantly different,18.74 mg/L in Group Ⅰ,133.67 mg/L in Group Ⅱ,and 257.43 mg/L in Group Ⅲ.C-reactive protein values among the groups were found to be highly and significantly correlated with the disease grade (P ＜ 0.01).After evaluating C-reactive protein levels according to the grade of the disease,Group Ⅱ was distinguished from Group Ⅰ with a cutoff C-reactive protein level of 72.54 mg/L,and from Group Ⅲ with a value of 195.85 mg/L.Those results were found to be statistically significant (P ＜ 0.01).Conclusion C-reactive protein can be accepted as a strong predictor in classifying different grades of the disease,and treatment can be reliably planned according to this classification.