Disclosed is a liquid-permeable panel that is of a toilet system for animals and that can prevent urine wetting resulting from torsion or folding over of a pee pad. The liquid-permeable panel (3) covers the excrement containment section (6) of the toilet system (1) for animals. Of the aforementioned panel, the side-surface 1 cm compression deformation load, which is the load necessary for at least 1cm of torsion to arise with respect to load from the side-surface direction (X) that is perpendicular to the direction of thickness of said panel, is at least 5 N and no greater than 20 N. Preferably, the liquid-permeable panel (3) has a plurality of holes (31) that penetrate said liquid-permeable panel (3) in the direction of thickness, and has as a material corrugated cardboard wherein liquid goes through the aforementioned plurality of holes (31), passing through in the direction of thickness of the aforementioned liquid-permeable panel.
