The invention discloses an aeration sewage treatment device and a method thereof. The aeration sewage treatment device comprises a controller, an aeration barrel (1), a motor (2), at least one impeller, a blast blower (5) and a sewage pipe (6), wherein openings are formed in the upper end and the lower end of the aeration barrel (1); the aeration barrel (1) is vertically arranged; the impeller is driven by the motor (2) to rotate; distances are formed between the opening in the lower end of the aeration barrel (1) and the bottom of a sewage pool or a riverway, and between the opening and the sludge; the impeller is arranged in the aeration barrel (1); the middle of the aeration barrel (1) is upwards communicated with at least one breather pipe (9) of which the upper end extends out of the water level; the breather pipe (9) is communicated with the blast blower (5); the sewage pipe (6) is connected with the opening in the lower end of the aeration barrel (1); the sewage pipe (6) is also connected with a flow sensor (7) and a flow control valve (8); and both the flow sensor (7) and the flow control valve (8) are controlled by a controller. The aeration sewage treatment device is energy-saving, environment-friendly and good in aeration sewage treatment effect; and eutrophic substances in the sludge can be purified.