Objective To investigate the diagnostic value of determination of pleural effusion or ascitic fluid,serum survivin contents for differentiating benign from malignant pleural effusion or ascites fluid and analyze the correlation between serum and pleural effusion or ascitic fluid.Methods22 patients with pleural effusion or ascites were detected for survivin level in serum,pleural effusion or ascites fluid.ELISA was taken to detect the survivin in serum,pleural effusion or ascites fluid.ResultsSurvivin of serum,pleural effusion or ascites fluid is elevated significantly in patients with tumors than those with benign dieases(P0.05).Survivin of serum is consistently increased with negative correlation with survivin level in pleural effusion or ascites fluid indicated by correlation analysis(P0.01).ConclusionSurvivin may be a valuable signal in the differentiating benign from malignant pleural effusion or ascites fluid.Determinate survivin of serum,pleural effusion or ascites fluid may be useful in the distinguishing of effusion or ascites.