To provide a purification apparatus which efficiently performs aerobic treatment and anaerobic treatment and reliably purifies organic polluted waste water, and to provide a purification method using the purification apparatus.

The purification apparatus 100 for purifying the organic polluted waste water, performs aerobic treatment by means of an aerobic microorganism and further performs anaerobic treatment by means of an anaerobic microorganism by utilizing flock formed during the aerobic treatment. The purification apparatus 100 is provided with: a treatment tank 1 storing the organic polluted waste water; a plurality of aeration means 5 which are arranged at intervals on a bottom portion 1a of the treatment tank 1; a multi-channel body 10 which is arranged between two adjacent aeration means 5 and performs aerobic treatment and anaerobic treatment; and a filtration means 20 which is composed of a plurality of filter materials that are arranged on each aeration means 5. Force of air from each aeration means 5 is suppressed by the filtration means 20. The present invention also provides the purification method using the purification apparatus 100.