PURPOSE: To obviate the generation of anions with liquid exclusive of water.

CONSTITUTION: This apparatus 1 for production of anions is constituted to form the air mixed with fine water drops by generating the fine water drops by a fine water drop producing machine 2 and simultaneously introducing the air at 0.5 to 50m/sec wind velocity by a fan 4 and to form the air mixed with the fine water drop by separating the fine water drops larger than at least 1μm grain size by a separator 5. The above-mentioned fine water drop producing machine 2 is provided with a water detecting sensor 3. As a result, the operation of at least either of the fine water drop producing machine 2 and the fan 4 is stopped upon discrimination that the detected liquid is not water; therefore, the anions are not generated with the liquid exclusive of the water.