In this study, chemical treatability of septa-e was investigated. The septage, taken from the equalization tank of an existing septa-e treatment plant, was coagulated by different chemicals such as alum, alum plus polyelectrolite (PE) and lime plus PE in varying dosages. After coagulation-flocculation and sedimentation TSS, COD and total phosphorus (TP) parameters of the liquid phase were measured. Capillay suction time (CST) was measured as an indication of the dewaterability of the sludge generated from coagulation. The best results were obtained by alum plus PE and the optimum dosages for alum and PE were found to be 200 mg/l and 2 mg/l, respectively. The COD and TSS removal efficiencies were satisfactory and the phosphorus concentration of the liquid phase was appropriate for the nutrient balance required by activated sludge microorganisms. Dewaterability of sludge was also at satisfactory levels. These results imply that dewaterability of sludge could be considered as an additional parameter for the determination of optimum coagulants.