A fluid-filled vibration damping device including: a partition member having first and second partition plates overlapping, and a holding area formed between overlapping surfaces of center parts of the two partition plates; and a movable membrane held and arranged in the holding area. A claw-shaped part and a perforation window are formed at respective corresponding positions of outer circumference parts of the two partition plates, and a fixing mechanism is constituted with the claw-shaped part latched in a circumference edge part of the perforation window. A widening area is provided between an outer circumference surface of the movable membrane and an inner circumference surface of the holding area by partially making a large distance therebetween. At least one of the two partition plates has a first air vent hole piercing a part constituting a wall part of the widening area.