Abstract: A fluid-filled vibration isolator includes a hollow, thick-walled, rubber body which opens downwardly, an annular side plate which has an upper part bonded to an outer surface of the rubber body, a bottom plate sealed to a lower end edge of the cylindrical side plate by caulking, a partition, and a rubber diaphragm. Peripheral edges of the partition and the diaphragm are both strongly sandwiched by the lower end edge to define a main fluid chamber between the rubber body and the partition and an auxiliary fluid chamber between the partition and the rubber diaphragm. A lower part of the side plate inclines obliquely and outwardly toward the lower end edges. A peripheral part of the partition bends into an L-shaped cross-section and contacts the obliquely and outwardly inclining lower part to define an annular space having a closed triangular cross-section. The annular space is blocked circumferentially by a projecting wall formed in the partition.