The present invention provides an air purifying apparatus that can continuously discharge sludge separated from suctioned contaminated air from a dust collecting apparatus to the outside, thereby improving convenience of use and air purifying performance, and can mix contaminated air with water, eliminate the sludge and contaminants in the air, and allow the eliminated sludge and contaminants to pass through a photocatalytic purifying unit and purify air using a photocatalytic reaction, thereby improving air purifying performance.
