The embodiment of the invention provides a control method and a control device for an air storage device, which are used for controlling an air storage device for storing air with quality meeting preset excellence standard. According to the embodiment, current air quality of outdoor air is monitored, on the premise that current air quality is prior to the air quality in the air storage device, air in the air storage device is replaced with outdoor air; on the premise that current air quality is not prior to the air quality in the air storage device but meets the preset excellence standard and the air storage device is not full of air, the outdoor air is stored to the air storage device; and on the premise that the current air quality meets the preset pollution standard, air in the air storage device is released to the room so as to purify indoor air. Therefore, according to the embodiment, excellent air can be stored and can be released to the room when pollution occurs, and compared with air purifying equipment, an air strainer is not used, thus avoiding the problem that the air strainer causes the purifying effect to become bad. In addition, the invention also provides an air treatment system.