It can consistently sterilize with people nearby; ultraviolet sterilization with long use period and high intensity; preliminary antibacterial and mildew-proof filter whose amount of air-flow is large and use period is long; photo catalyst (TIO2) and activated carbon can sterilize and remove odor: anion can purify the air; the speed of air-flow(quick,moderate, slow) is adjustable and the direction of air-flow is diverse and cycling; automatic operation controlled by micro-computer; automatic record and manifestation of working time; operation by remote control of far infrared.