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In this study, the treatment of domestic wastewater in a field-scale membrane submerged intermittently aerated activated sludge process(210 ㎥/day) was investigated under difference aeration methods. Operating temperature was 5.4 to 25.0℃ and membrane used in this study is a polyethylene hollow fiber membrane(pore size 0.4 ㎛). The range of operating flux was 9.7~24.4 ℓ/㎡-h and membrane permeates periodically operated for 7 min followed idle for 3 min. The results showed that MIA(modified intermittent aeration) was more efficient in nitrogen and phosphorus removal. The removal efficiencies of T-N and T-P were 73.0 % and 69.6 % for CIA(conventional intermittent aeration) and 57.5 %, 58.6 % for MIA(modified intermittent aeration). With application of modified intermittent aeration, DO reached nearly 0 ㎎/ℓ within 10 minutes after air off. Organics of influent could be entirely consumed to the denitrification and the P-release without the influence by remained DO in intermittent aeration reactor. Therefore, newly developed KSMBR(Kowaco-KMS-Ssangyoung Membrane Bio-Reactor) process with modified intermittent aeration can be one of the useful process for stable nitrogen and phosphorus removal.