PROBLEM TO BE SOLVED: To provide a dry type methane fermentation residue dehydration system capable of efficiently performing dry type methane fermentation while keeping a constant concentration of sludge even when using raw material containing impurities, and operating a dehydration apparatus with a stable dehydration capacity. SOLUTION: The dry type methane fermentation residue dehydration system includes: a methane fermentation tank for dry methane-fermenting organic waste; an impurity separation means for separating the impurities contained in the fermentation residue of the organic waste; a dehydration means for dehydrating the fermentation residue separated from the impurities; and a dehydrated sludge returning means for returning the dehydrated sludge to the methane fermentation tank. The fermentation residue of the organic waste caused in the methane fermentation tank is fed to the impurity separation means, and the fermentation residue separated from the impurities is fed to the dehydration means. A