Abstract: The present invention is directed to a wood preservative composition and a method of using the same. The wood preservative composition has an effective amount of a fungicidal and bactericidal metal compound, a triazole compound, and at least a first and/or a second quaternary ammonium compound. Alternatively, the wood preservative composition contains at least one additional agent, depending on the formulation. In one embodiment, the composition contains a mold inhibitor that is emulsified with the metal from the fungicidal and bactericidal metal compound in solution. In another embodiment, there is an effective amount of a boron compound. And in another embodiment, a combination of the boron compound and at least one amine compound.