In a table tennis ball-sorting device, a plurality of rails are disposed side by side in substantially a horizontal direction along the side of at least one playing surface of a table tennis table at intervals that are capable of having passed therethrough only deformed balls, and a plurality of rails are disposed side by side in substantially a horizontal direction along the rear part of the playing surface at intervals that are capable of having passed therethrough only deformed balls. The former rails are disposed to be inclined towards downstream, while the downstream side thereof is overlapped on the upstream part of the latter rails so that balls can be transferred. A table tennis apparatus using the table tennis ball-sorting device is also disclosed.