The present invention relates to a sterilizing device. More specifically, the sterilizing device comprises: a bubble generating pipe having a structure for changing a flow rate of a fluid flowing therein； and an ultrasonic wave generating device coupled with the bubble generating pipe, and maximizing the generation of bubbles. The bubble generating pipe comprises: a connection part which has an inlet part having a rear side end part axially inclined, has an outlet part having a front side end part axially inclined, has a separation space between the rear side end of the inlet part and the front side end of the outlet part, has one end coupled with the rear side end part of the inlet part, has the other end coupled with the front side end part of the inlet part, connects the rear side end part of the inlet part and the front side end part of the outlet part, and has a gas feeding hole penetrating from one surface to the other surface； and a spatial part which is formed by the outer surface of the rear side end part of the inlet part, the outer surface of the front side end part of the outlet part, and the inner surface of the connection part, communicates with the gas feeding hole, immediately promotes the inflow of a gas when pressure in a pipe decreases, and prevents a backflow. The ultrasonic wave generating device comprises: an oscillating unit provided with electrical power and generating vibration； a vibrating unit vibrated by being coupled with the oscillating unit； and a cooling hole penetrating through the vibrating unit and the oscillating unit. The vibrating unit and the oscillating unit are cooled by air or by water according to the position of the ultrasonic wave generating device coupled with the bubble generating pipe.본 발명은 살균장치에 관한 것으로, 더욱 상세하게는, 내부에 흐르는 유체의 유속을 변화시키는 구조를 가지는 버블발생관과, 상기 버블발생관에 결합되어 버블 생성을 극대화하는 초음파 발생장치를 포함하고, 상기 버블발생관은, 후측단부분이 축경되는 구조를 가지는 유입부와, 전측단부분이 축경되는 구조를 가지는 유출부와, 상기 유입부의 후측단과 상기 유출부의 전측단 사이의 이격공간을 형성하며, 일단은 상기 유입부의 후측단부분에 결합하
