The removal efficiency of COD, N and P from synthetic wastewater using subsurface-flow constructed wetland were evaluated and N, P accumulation in wetland with either sand and soil or slate and sand medium were studies. Two types of wastewater contained COD, N and P concentration in wastewater at 500, 20, 5 mg/1 and 500, 40, 10 mg/1 respectively were used in this study. The retention time and flow rate were set at 5 day and 25 1/d respectively. In addition, N and P in various parts of the system which included medium and plant (Typha angustifolia) were studied. The result showed that, the constructed wetland with both media types could removed COD, N and P from wastewater to thai housing standard of effluent. The best removal efficiency for COD and N was found in sand and soil medium (94.23% and 94.59% respectively) but the best removal efficiency for P was found in constructed wetland with slate and sand medium (74.67%), wetland with Typha angustifolia and control unit have the same treatment efficiency COD while the wetland with Typha angustifolia was higher treatability of N, P . Most N, P in influent was adsorbed on medium. For constructed wetland with sand and soil medium N and P accumulated was 65.3% and 36.0% respectively, and for constructed wetland with slate and sand medium N, P accumulated was 53.8% and 41.1% respectively. The best removal efficiency of sand and soil medium can be achieved when feeding wastewater at COD concentration of 500 mg/1, N 40 mg/1 and P 10 mg/1 and the best removal efficiency of constructed wetland with slate and sand medium can be achieved when feeding wastewater at COD concentration of 500 mg/1, N 20 mg/1 and p 5 mg/1.