The nitrogen removal characteristics of the MBR system consisted of two intermittent reactors, a membrane reactor and a deaeration reactor under constant flow and wastewater composition at different operational temperature and SRTs (Sludge Retention Times) were studied by computer simulation. The nitrogen removal efficiencies were dropped from 59% to 31%, when operational temperature was increased to $25^{circ}C$ from $13^{circ}C$ with same SRT of 25 days. Lower RBO (Readily Biodegradable Organic) concentrations at intermittent reactors at $25^{circ}C$ compared with those at $13^{circ}C$ of operational temperature were believed to be the main cause. The nitrogen removal efficiencies and RBO concentrations at each intermittent reactors were recovered when SRT was reduced to 12.6 days at $25^{circ}C$. The effect of both SRT and operational temperature on RBO concentrations at intermittent reactors is need to be studied further.