An astride-type small boat sails on water under propulsive forces generated by a propulsion unit driven by an engine mounted in a hull assembly. A driver's seat is disposed on the hull assembly rearwardly of a steering device mounted thereon, with foot spaces defined on opposite sides of said driver's seat. A passenger's seat displaced from the driver's seat in a transverse direction of the hull assembly. The passenger's seat is displaced from the driver's seat in a fore-and-aft direction of the hull assembly.