This study was carried out to investigate the removal of nitrogen and phosphorus in municipal sewage depending on existence of biological coated media in BCM reactor. The reactor with biological coated media is the process combining $A_2/O$ process. The removal efficiencies for $COD_{Mn},; BOD_5,;SS$, T-N and T-P were $78\%,;90.5\%,;92.3\%,;61.9\%,;60.2\%$, respectively. The specific nitrification rate$(mgNO_3-N/gMLSS{cdot}d)$ of Contact aeration basin was 52.2 and the specific denitrification rate$(mgNO_3N/gMLSS{cdot}d)$ in anoxic basin was 95.1. Also, phosphorus release$(mgPO_4-P/gMLSS{cdot}d)$ in Anaerobic basin was 71.8 and Phosphorus uptake$(mgPO_4-P/gMLSS{cdot}d)$ in contact aeration was 27.1.