[Object] To provide an ozonized water producing apparatus capable of efficiently and easily producing ozonized water with a high dissolution degree and a high concentration. [Solution] In an ozonized water producing apparatus (201) constituted by including a pipeline (273) for passing water to be treated through, a gas-liquid mixing structure (205) provided halfway in the pipeline, and an ozone supply structure (203) for supplying ozone into the gas-liquid mixing structure, the gas-liquid mixing structure is provided with a magnet (243) for exerting a magnetic force onto an inside. By causing the magnetic force to act on both the water to be treated and ozone, ozonized water with a high dissolution degree and a high concentration can be efficiently and easily produced.본 발명은, 오존수로부터의 오존 탈기를 유효 저지함에 의해, 사람과 가축에 대해 악영향을 줄 우려가 없는 가축의 소독 방법을 제공하며, 이를 위한 해결수단으로서, 함유 오존 기포의 입경(R)이, 0
