Objective To optimize the cytological inspection of pleural effusion and ascites. Methods Based on single factor analysis and orthogonal test,the inspection of pleural effusion and ascites in- cluding specimen volume,the frequency of inspection and diagnosis of the original sites were analyzed. Results The optimal inspection was performed with four times,40 ml of specimen and clinical evidences for o- riginal sites.Conclusion Optimal conditions for the cytological inspection of pleural effusion and ascites are satisfying and feasible.