In this study, the properties of wastewater sludge inspected using a simple meacurement method, CST(Capillary Suction Time) for dewaterability. It suggested to utilize optimum polymer and drainage conditions of wastewater in the printing paper and tissue paper mill. Since the optimal dosage of polymer was detrmined with the value of CST, COD removal efficiency, and floc strength, it cam be more economical by reducing the amount of polymer. The CST can be obtained within several seconds, it can relatively measure dewaterability in precise. Moreover, it can also be useful n investigating the optimal dosage.