Without causing unnecessary turbulence and fluid flow in a fluid, is to provide a supply possible fine bubble generator to the fluid in the fluid of fine air bubbles of mass. Micro bubble generator (11), can be placed in a state in which the casing of rectangular shape (11a) inside, (28a, 28b) between each discharge ports facing each other, fine bubbles generating part of the two (12, 13) has been formed. Fine bubble generation section (12, 13), fluid swirl chamber formed de (25a, 25b) and the partition wall provided at both ends of the peripheral wall which is provided so as to surround the imaginary center line (25c) and (25d) ( (18a, and 18b) liquid introduction path provided in communication (25) a fluid swirl chamber for 25), and introducing a liquid along a direction forming a skewed imaginary center line for (25c), discharge ports (14a, 14b) and the gas introduction path opened partition wall (25) to (25a) each of the fluid swirl chamber for introducing the gas (25) within each fluid swirl chamber was opened partition walls (25b) Im with (28a, 28b) and a.流体中に不要な液流や乱流を発生させずに、大量の微細気泡混じりの流体を当該流体中へ供給可能な微細気泡発生器を提供する。微細気泡発生器(11)は、直方体形状のケーシング(11a)内に、二つの微細気泡発生部(12,13)を、各吐出口(28a,28b)同士が互いに対向する状態で配置して形成している。微細気泡発生部(12,13)は、仮想中心線(25c)を包囲して設けられた周壁(25d)とその両端に設けられた隔壁(25a,25b)とで形成された流体旋回室(25)と、仮想中心線(25c)に対してねじれの位置をなす方向に沿って液体を導入するため流体旋回室(25)に連通して設けられた液体導入経路(18a,18b)と、各流体旋回室(25)内に気体を導入するため各流体旋回室(25)の隔壁(25a)に開設された気体導入経路(14a,14b)と、隔壁(25b)に開設された吐出口(28a,28b)と、を備えている。
