Objective To explore the clinical value of flow cytometry( FCM) and DNA automated cell image analyzer ( AICM) in determine the character of ascites and pleural effusion.Methods This was a cross-sectional study.203 ascites and pleural effusionsamples were random selected from PLA hospital inpatients between August 2013 to June 2014 .The DNA content of sediment cells were detectedthrough the FCM and AICM respectively benign and malignant disease were differentiated according the counts and proportion of aneuploid cells.The sensitivity, specificitywere calculated byROC curves.Results The sensitivity, specificity and accuracy of flow cytometry cell in detectingtumor cells were 78.6%,80.0% and 79.2%%, while the sensitivity, specificity and accuracy of image analyzer were 83.5%,78.6% and 81. 3%respectively.When FCM and AICMwere combined ,the sensitivity, specificity and accuracyincreased to 92.2%, 86.3% and 89.6%.Conclusions Compared toconventional cytology test, the sensitivity and specificity were significantly high when the two methods were combined .Therefore, the combination method can be used to assist in clinical identification of the nature of ascites and pleural effusion and to help the diagnosis of disease.