The invention discloses a multifunctional ultrasonic humidifier which comprises a base, a water tank, an atomizing device mounted in the base, a pneumatic device, an
ozone generating device and a negative
ion generating device, wherein the
ozone generating device is used for generating
ozone, generated ozone is input into water of the water tank through an ozone channel, and
bacteria, viruses and other pollutants in water are decomposed and killed through ozone, so that water is clean and free of
pollution, and therefore water mists generated by water do not carry
bacteria and viruses, and are harmless on a
human body; the negative
ion outlet end of the negative
ion generating device extends into an air outlet channel, and the pneumatic device blows out air from the air outlet channel for blowing out the generated negative ions, so that the structure is simple; and the negative ions are mixed with water mists generated by humidifying to
blow out from a steam outlet channel, so that the purpose of humidifying the negative ions is achieved, and therefore, the environment is fresh and healthy.