The Ministry of Environment of Korea has strengthened effluent standard of total nitrogen and phosphorus concentration at the sewage treatment plants (STP5) since 2012. Effluent total phosphorus concentration is able to control by post physicochemical treatment, however total nitrogen that is treated biological process is hard to meet the standard because of low nitrification rate in winter. This research aim to predict the removable influent T-N concentration based on the water temperature and wastewater flow rate by analysing specific nitrification rate (SNR) and control the STPs efficiently. The results of this study, SNR was from 1.1 to 2.3 mgNH4-N/gMI.VSS/hr at 13.6-25.3 t. and temperature and SNR was shown the linear relationship, if nitrate is removed completely, although NI-14-N is contained the effluent T-N, it will be able to lower the effluent T-N, In that case, the maximum inflow T-N was predicted 51 mg/L at 13 t, the effluent NH4-N was predicted 5 mg/L under fully denitrification conditions, ln winter, it is desirable to control process using operational factors such as simulated MLSS. HRTox by removable T-N concentration based on the SNR results.