The present invention relates to a water bicycle using a floating body and to a drive housing used for same. The water bicycle according to the present invention includes: a plurality of floating bodies having a spherical or a substantially spherical shape and which are disposed at front and rear positions; connection rods attached to or detached from the respective floating bodies at positions directed toward the central part of the plurality of floating bodies; a main body frame connecting the connection rods with each other; a chair for the driver disposed on the main body frame, a handle disposed at a position where the handle can be operated while said chair is occupied by a driver and which is connected to a key that is oriented underwater in the rear part of the water bicycle; and pedals disposed on the main body frame, positioned so as to be tilted forward, and which provide a driving force so that the water bicycle can move forward.