A cast strip withdrawing apparatus includes a plurality of pairs of rolls, and retains and withdraws a dummy bar via a fixed-side roll and pressure-side roll, which face each other, of each of these pairs of rolls. Each of the pressure-side rolls includes a fluid pressure cylinder imparting a dummy bar retaining pressure. A source pressure side fluid line supplying fluid pressure to these fluid pressure cylinders includes: a first pressure-reduction unit, a pressure drop detection unit, a line isolating unit installed on a source pressure side of the pressure drop detection unit, and a bypass unit.