The invention relates to an all-sealed vibration damping and water preventing device with large regulating quantity, which is mainly used for a cable-stayed bridge, a suspension bridge, an arch bridge and other span structures. The all-sealed vibration damping and water preventing device is in an upper and lower flange structure and comprises an upper flange (4), a lower flange (2) and a sleeve (6), wherein the upper flange (4) and the lower flange (2) are arranged up and down; the upper flange (4) is fixedly sleeved at the lower part of the sleeve (6); a rubber gasket (3) is embedded betweenthe upper flange (4) and the lower flange (2); the sleeve (6) is internally provided with a vibration damper or a rubber centering ring (10); a first sealant (11) is filled between the vibration damper or the rubber centering ring (10) and a sleeve opening positioned on the outlet end of the sleeve (6); the end surface of the first sealant (11) is in the shape of a round table; and the outlet endof the sleeve (6) is provided with a water preventing cover (7), and a rubber sealing ring (12) and a second sealant (13) are adopted to carry out two-end seal on an upper port and a lower port of the water preventing cover (7). The all-sealed vibration damping and water preventing device ensures the sealing protection effect of a bridge in the actual operation process and meets the requirements on a long-life system of the bridge.