To obtain a fish-gathering agent exhibiting its effect in a short period of time and having a small effect imparting to an environment.

This fish-gathering agent is obtained by mixing a carbon dioxide gas-generating agent with a fish-attracting agent having a smell or a taste which is a fond of a fish and solidifying as a particle state. It can be simply poured in water on its use, and since carbon dioxide gas is generated in a large amount, the fish-gathering agent rapidly spreads by that energy and its effect is exhibited in a short period of time. Since the raw materials are dissolved in water and no solid material remains, it does not become a cause of polluting or destroying an environment as those of conventional ground baits.