A liquid-sealed antivibration device comprising: a first mounting member, a second mounting member having a cylindrical shape; a vibration-isolating base body which connects the first mounting member and the second mounting member and is made of a rubbery elastic material; a diaphragm formed of a rubbery elastic film which is mounted on the second mounting member so as to form a liquid sealed chamber between the diaphragm and the vibration-isolating base body; a partition element which partitions the liquid sealed chamber into a first liquid chamber on a vibration-isolating base body side and a second liquid chamber on a diaphragm side; and an orifice flow passage which allows the first liquid chamber and the second liquid chamber to be communicated with each other, wherein the partition element comprises: an annular orifice forming member which is mounted on an inner side of a peripheral wall portion of the second mounting member and forms the orifice flow passage; an elastic wall which blocks a space formed within an inner peripheral surface of the orifice forming member and is made of a rubbery elastic material; and a pair of partition plates (48, 50) which are connected to each other via a connecting portion which penetrates a radially central portion of the elastic wall, and sandwich the elastic wall in the axial direction of the elastic wall, wherein a through hole which penetrates at least one of the partition plates in the axial direction is formed on a radially outer side of the connecting portion, and the pair of partition plates (48, 50) has sandwiching portions which sandwich the elastic wall on a radially outer side of the connecting portion, characterised in that the elastic wall has a recessed portion on at least one of front and back wall surfaces of the elastic wall at an elastic wall portion sandwiched by the sandwiching portions, and the through hole is formed at a position where the through hole overlaps with the recessed portion in the axial direction. a first mounting member, a second mounting member having a cylindrical shape; a vibration-isolating base body which connects the first mounting member and the second mounting member and is made of a rubbery elastic material; a diaphragm formed of a rubbery elastic film which is mounted on the second mounting member so as to form a liquid sealed chamber between the diaphragm and the vibration-isolating base body; a partition element which partitions the liquid sealed chamber into a first liquid chamber on a vibration-isolating base body side and a second liquid chamber on a diaphragm side; and an orifice flow passage which allows the first liquid chamber and the second liquid chamber to be communicated with each other, wherein the partition element comprises: an annular orifice forming member which is mounted on an inner side of a peripheral wall portion of the second mounting member and forms the orifice flow passage; an elastic wall which blocks a space formed within an inner peripheral surface of the orifice forming member and is made of a rubbery elastic material; and a pair of partition plates (48, 50) which are connected to each other via a connecting portion which penetrates a radially central portion of the elastic wall, and sandwich the elastic wall in the axial direction of the elastic wall, wherein an annular orifice forming member which is mounted on an inner side of a peripheral wall portion of the second mounting member and forms the orifice flow passage; an elastic wall which blocks a space formed within an inner peripheral surface of the orifice forming member and is made of a rubbery elastic material; and a pair of partition plates (48, 50) which are connected to each other via a connecting portion which penetrates a radially central portion of the elastic wall, and sandwich the elastic wall in the axial direction of the elastic wall, wherein a through hole which penetrates at least one of the partition plates in the axial direction is formed on a radially outer side of the connecting portion, and the pair of partition plates (48, 50) has sandwiching portions which sandwich the elastic wall on a radially outer side of the connecting portion, characterised in that the elastic wall has a recessed portion on at least one of front and back wall surfaces of the elastic wall at an elastic wall portion sandwiched by the sandwiching portions, and the through hole is formed at a position where the through hole overlaps with the recessed portion in the axial direction.