Without using any pumps and controlling devices, to control microorganism's activity by supplying an activity controlling substance which is necessitated for the microorganism activity is realized. A microbial activity controlling material 3 is filled into a vessel 4 having a sealed structure and at least a part of which is provided with a non-porous film 2, and then, the microbial activity controlling material 3 is supplied through the non-porous film 2 part of the vessel 4 to ambient places around the vessel 4 at the speed controlled by the molecular permeation performance of the non-porous film 2, and thereby the activities of microorganisms residing around the vessel is controlled. The microbial activity controlling material 3 is at least one of materials which function as electron donor being of an energy source of microorganism, acidic materials, basic materials, inorganic salts, oxygen releasing materials and oxygen absorbing materials, except combinations of acidic materials and basic materials and combinations of oxygen releasing materials and oxygen absorbing materials.