NOVELTY - Rhodanobacter sub white 2CGMCC No.5283 for removing ammonia nitrogen in sewage at low temperature under aerobic conditions, is new.    USE - Rhodanobacter is useful for removing ammonia nitrogen in sewage at low temperature under aerobic conditions (claimed).    ADVANTAGE - The method: has ammonia nitrogen removal rate of 10%; has maximum effluent ammonia nitrogen concentration of 4.2 mg/l and better than the first-level A effluent standard (when the water temperature is less than or equal to to 12 degrees C, and the control index of first-level A standard is 8 mg/l).    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for separation culture of Rhodanobacter, comprising: (a) adding first nitrous acid bacterium culture solution into a small scale sequencing batch reactor (SBR), inoculating sewage into a sewage treatment plant in the first nitrous acid bacterium culture solution, continuously culturing at 8-12 degrees C for 4-6 days, taking liquid supernatant, adding second nitrous acid bacterium culture solution, continuously culturing at 8-12 degrees C for 4-6 days, taking liquid supernatant, adding third nitrous acid bacterium culture solution, continuously culturing at 8-12 degrees C for 4-6 days, enriching and acclimatizing low temperature bacterium, (b) taking sludge (10 ml), adding into 250 ml conical flask filled with sterilized distilled water (90 ml) and 20-30 sterilized glass beads, shaking for 10-30 minutes so that the bacterial cell is completely released in the liquid supernatant, allowing to stand for 20-40 minutes, adding liquid supernatant (1 ml) to the test tube filled with sterilized distilled water (9 ml) to obtain 10-2 of bacterial suspension liquid, diluting until a dilution factor of 10-8, (c) selecting 10-5 to 10-8 bacterial suspension liquids, inoculating bacterial suspension liquid (1 ml) on nitrous acid bacterium solid culture medium, processing three parallel samples for each dilution and numbering, moisturizing and culturing in aerobic condition at 10 degrees C for 2-3 weeks, and (d) picking large bacterial colonies from the culture medium and different single bacterial colonies, marking off and separating, repeatedly marking and separating for 3-4 times so that the bacterial colony on the plat has different types in microscope and the single and similar bacterial colony is single bacterial colony, identifying, and confirming Rhodanobacter.