A water bike using a floating bodies and a driving housing is provided. Some implementations of the disclosed technology provide the water bike including a plurality of floating bodies each of which has a spherical shape or a sphere-like shape and disposed at front and rear sides of the water bike, connection rods that are attached to or detached from the floating bodies at positions toward centers of the floating bodies, a body frame for connecting the plurality of floating bodies to one another, a driver chair disposed over the body frame, handles configured to manipulate a moving direction and connected to a rudder that is disposed at a rear side of the water bike, and pedals disposed on the body frame adjacent to the floating body that is disposed at the front side to provide a driving force.