Filtration methods of recent vacuum cleaner are either filter paper type or paper bag type, but in both methods all dusts had not been perfectly filtered. Very fine dust, less than the size of ten microns, was discharged with ventilation in room and it is usually called 'house dust'. Sometimes, house dust includes excrement of tick and mold. In order to clean exhaust, we provided a new type charged filter on exhaust port. This filter caught all dusts larger than two microns. Furthermore, we treated the inside filter of the double paper bag with chemicals to preserve multiplication of tick, mold, bacillus in dusts.