Abstract: 【Objective】 To explore the value and significance of COX-2 mRNA in differential diagnosis of ascites by detecting the expression level of COX-2 mRNA in ascites. 【Method】 49 cases of ascites were collected from June 2014 to February 2015 in our hospital

including 43 cases of malignant ascites and 15 cases of benign ascites. Expression level of COX-2 mRNA in ascites were detected by fluorescence quantitative PCR technology

compared the difference of expression level of COX-2 mRNA in malignant ascites and benign ascites

and the expression level in different kind of cause. 【Results】 34 cases of malignant ascites and 15 cases of benign ascites were all amplified COX-2 and GAPDH. The expression level of COX-2 mRNA in malignant and benign ascites had no relationship with gender and age(P > 0.05). Expression level of COX-2 mRNA in malignant ascites and benign ascites were 7.93(5.04

16.58) and 0.95(0.57

1.79) respectively

difference being statistically significant (P < 0.05). Expression level of COX-2 mRNA in malignant ascites were different in different kinds of primary tumors (P > 0.05). Expression level of COX-2 mRNA in benign ascites were not significant difference between liver cirrhosis and tuberculous peritonitis (P > 0.05). 【Conclusion】 High COX-2 mRNA expression was found in malignant ascites

which were higher than in benign ascites

it will be great significance in the differential diagnosis of malignant ascites and benign ascites.