A fluid-filled type vibration damping device including: a primary fluid chamber partially constituted by a main rubber elastic body connecting a first and second mounting member; an equilibrium chamber partially constituted by a flexible film; a partition member supported by the second mounting member; and a partition rubber film is superimposed against the partition member and secured interlocking with an annular interlocking projection projecting from the partition member. A first seal rubber is compressed between the interlocking projection and the tubular fitting member and extending about the entire circumference, thereby forming a working air chamber therebetween. A gap is furnished between and a second seal rubber is compressed between the tubular fitting member and the orifice member, and extending about the entire circumference.