A sailing ship includes a sailing unit, which comprises a hard sail assembly comprising a plurality of hard sail sections of wing-shaped hollow cross section vertically stacked so each, except the lowermost, fits on the one immediately below; a mast assembly comprising a plurality of mast sections of hollow cross section vertically stacked so each, except the lowermost, fits in the one immediately below; connecting members for connecting upper ends of the hard sail sections to upper ends of the mast sections located at the same level; first means for moving each mast section, except the lowermost, toward and away from the one immediately below; and second means for rotating the mast assembly around its longitudinal axis. Overlapping lengths between vertically adjacent mast sections are variably controlled so as to variably control overlapping lengths between vertically adjacent hard sail sections. Thus, the hard sail assembly vertically expands and contracts.