The invention discloses a fiber hydrophone protection structure for a target ship. The fiber hydrophone protection structure comprises: a hand wheel drive mechanism and a swing lever downward-releasing mechanism. The hand wheel drive mechanism comprises: a truss, a hand wheel, a lead screw, a first revolute pair, and a second revolute pair. The swing lever downward-releasing mechanism comprises a base, a third revolute pair, a swing lever, a device mounting bin and a cable. The base is connected with one end of the swing lever via the third revolute pair. The device mounting bin is connected with the other end of the swing lever. The swing lever is hollow and the cable passes through the interior of the swing lever. The other end of the second revolute pair is connected to the swing lever. The fiber hydrophone protection structure for a target ship replaces the widely used rope suspension in the external-field test of the fiber hydrophone, greatly improves the safety and reliability of the external-field test of the fiber hydrophone.