To easily bind a folded body formed by flattening a hose for a fire hose and alternately folding back the flattened hose at each predetermined length, and allow the unbound hose to be attached to the fire hose to prevent the hose from being lost.

The binder comprises: a belt 10 formed of a belt member to be wound around nearly the center of a folded body 4 which is obtained by flattening a hose 1 and alternately folding back the flattened hose 1 and which has a water-supply-side connecting metal fitting 2 and a water-discharge-side connecting metal fitting 3 positioned at nearly the centers of both sides of the folded body 4, respectively; a looped holder 20 which is provided at the belt 10 and held by the water-supply-side connecting metal fitting 2 passed therethrough; and a connector 30 which detachably connects one end 11 and the other end 12 of the belt 10.