To easily separate suspended matter from livestock feces and urine.

This suspended matter separation apparatus is provided with a mixing means 400 mixing a solution 100 containing suspended matter with liquid 200 of low specific gravity to dissolve the liquid in a solvent; and a centrifugal separator 500 centrifugally separating the solution mixed by the mixing means and to separate the suspended matter from the solution. The liquid having a lower specific gravity than that of the solvent in the solution containing the suspended matter is added to the solution to dissolve it into the solvent, then the suspended matter in the solution is centrifugally separated. By this method, the specific gravity of the solvent is lowered by mixing with the liquid of low specific gravity, a difference of specific gravities becomes large, to thereby easily centrifugally separate the suspended matter. As an inorganic coagulant is not needed, addition of chemicals is not necessary for pH adjustment after treatment. The added liquid of low specific gravity can be easily recovered, to reduce an environmental load.