A torque fluctuation reducing apparatus, comprising: a first main damper provided on a power transmission path between a drive source and a transmission, and reducing, by using an elastic force, fluctuation torque generated between the drive source and the transmission; a second main damper provided at a transmission-side relative to the first main damper to be in series with the first main damper on the power transmission path, and reducing, by using an elastic force, the fluctuation torque generated between the drive source and the transmission, the second main damper including a vibration damping property which is different from a vibration damping property of the first main damper; a dynamic damper (3c, 3d) provided on the power transmission path between the first main damper and the second main damper, and restricting vibration at a specific resonance point of a drive system on the power transmission path by using an inertia body (34d, 35, 45c) and an elastic force; a chamber accommodating the first main damper and the second main damper, and the dynamic damper (3c, 3d); and a viscous medium enclosed in part of the chamber, characterized in that an inertia body portion of a center plate is provided with: a radially-recessed-and-protruding portion at an outer circumferential end surface of the inertia body portion, wherein the radially-recessed-and-protruding portion is formed in a gear configuration which includes recess and protrusion in the radial direction; or an axially-recessed-and-protruding portion which includes recess and protrusion in the axial direction, wherein the axially-recessed-and-protruding portion is configured by punching so that the protrusion is formed at a surface of one side of the inertia body portion and the recess is formed at a surface of the opposite side of the inertia body portion; wherein the recessed-and-protruding portion (34e, 34f) is set to be immersed in or be in contact with the viscous medium in the chamber so that resistance occurring when the inertia body portion moves in the viscous medium is increased. a first main damper provided on a power transmission path between a drive source and a transmission, and reducing, by using an elastic force, fluctuation torque generated between the drive source and the transmission; a second main damper provided at a transmission-side relative to the first main damper to be in series with the first main damper on the power transmission path, and reducing, by using an elastic force, the fluctuation torque generated between the drive source and the transmission, the second main damper including a vibration damping property which is different from a vibration damping property of the first main damper; a dynamic damper (3c, 3d) provided on the power transmission path between the first main damper and the second main damper, and restricting vibration at a specific resonance point of a drive system on the power transmission path by using an inertia body (34d, 35, 45c) and an elastic force; a chamber accommodating the first main damper and the second main damper, and the dynamic damper (3c, 3d); and a viscous medium enclosed in part of the chamber, characterized in that an inertia body portion of a center plate is provided with: a radially-recessed-and-protruding portion at an outer circumferential end surface of the inertia body portion, wherein the radially-recessed-and-protruding portion is formed in a gear configuration which includes recess and protrusion in the radial direction; or an axially-recessed-and-protruding portion which includes recess and protrusion in the axial direction, wherein the axially-recessed-and-protruding portion is configured by punching so that the protrusion is formed at a surface of one side of the inertia body portion and the recess is formed at a surface of the opposite side of the inertia body portion; wherein the recessed-and-protruding portion (34e, 34f) is set to be immersed in or be in contact with the viscous medium in the chamber so that resistance occurring when the inertia body portion moves in the viscous medium is increased. a radially-recessed-and-protruding portion at an outer circumferential end surface of the inertia body portion, wherein the radially-recessed-and-protruding portion is formed in a gear configuration which includes recess and protrusion in the radial direction; or an axially-recessed-and-protruding portion which includes recess and protrusion in the axial direction, wherein the axially-recessed-and-protruding portion is configured by punching so that the protrusion is formed at a surface of one side of the inertia body portion and the recess is formed at a surface of the opposite side of the inertia body portion; wherein the recessed-and-protruding portion (34e, 34f) is set to be immersed in or be in contact with the viscous medium in the chamber so that resistance occurring when the inertia body portion moves in the viscous medium is increased.