To provide a formaldehyde decomposer which reduces the production cost with the use of a high safety microbial bacterium, is entirely pollution-free and does not affect the environment and the human body on its production or in use, has persistence in use, and furthermore can efficiently decompose formaldehyde, and its use method.

The formaldehyde decomposer has a powder obtained by mixing a Bacillus sphaericus microbial bacterium, a Bacillus subtilis microbial bacterium or a Bacillus thuringiensis microbial bacterium with livestock feces which have been subjected to high temperature treatment at 60-150°C. The formaldehyde decomposer is a liquid obtained by adding water to the powder or is obtained by absorbing the liquid in at least one of a water-absorbing gelling agent and gelatin and agar.

COPYRIGHT: (C)2008,JPO&INPIT