A valve timing control apparatus of an internal combustion engine, comprising: a driving rotational body to which torque is transmitted from a crankshaft; a driven rotational body fixed to a camshaft to which torque is transmitted from the driving rotational body; an electric motor disposed between the driving rotational body and the driven rotational body and relatively rotating the driving rotational body and the driven rotational body when electric power is applied thereto; and a deceleration mechanism that decelerates a rotational speed of the electrical motor and transmit the decelerated rotational speed to the driven rotational body, wherein the decelerator includes: an eccentric rotational shaft that receives torque of the electrical motor and is eccentric-rotated; a bearing portion disposed at an outer circumference of the eccentric rotational shaft; an inner tooth formation part integrally disposed at at least one of the driving rotational body and the driven rotational body and to which a plurality of inner teeth are provided at an inner circumference of the inner tooth formation part; a plurality of power transmission bodies that are power-transmissibly disposed between an outer circumferential surface of an outer wheel of the bearing portion and the respective inner teeth of the inner tooth formation part, wherein an engaged portion of the inner tooth moves in a circumferential direction by eccentric rotation of the eccentric rotational shaft; and a maintaining member integrally disposed at a remaining one of the driving rotational body and the driven rotational body, separating respective power transmission bodies, and allowing the respective power transmission bodies to move in a radial direction, wherein a recess portion is formed at at least one of the outer circumference of the eccentric rotational shaft and an inner circumference of the bearing portion, and a pressing member that allows the power transmission body to generate power in a tooth bottom surface direction of the inner tooth through the bearing portion is disposed at the recess portion. a driving rotational body to which torque is transmitted from a crankshaft; a driven rotational body fixed to a camshaft to which torque is transmitted from the driving rotational body; an electric motor disposed between the driving rotational body and the driven rotational body and relatively rotating the driving rotational body and the driven rotational body when electric power is applied thereto; and a deceleration mechanism that decelerates a rotational speed of the electrical motor and transmit the decelerated rotational speed to the driven rotational body, wherein the decelerator includes: an eccentric rotational shaft that receives torque of the electrical motor and is eccentric-rotated; a bearing portion disposed at an outer circumference of the eccentric rotational shaft; an inner tooth formation part integrally disposed at at least one of the driving rotational body and the driven rotational body and to which a plurality of inner teeth are provided at an inner circumference of the inner tooth formation part; a plurality of power transmission bodies that are power-transmissibly disposed between an outer circumferential surface of an outer wheel of the bearing portion and the respective inner teeth of the inner tooth formation part, wherein an engaged portion of the inner tooth moves in a circumferential direction by eccentric rotation of the eccentric rotational shaft; and a maintaining member integrally disposed at a remaining one of the driving rotational body and the driven rotational body, separating respective power transmission bodies, and allowing the respective power transmission bodies to move in a radial direction, an eccentric rotational shaft that receives torque of the electrical motor and is eccentric-rotated; a bearing portion disposed at an outer circumference of the eccentric rotational shaft; an inner tooth formation part integrally disposed at at least one of the driving rotational body and the driven rotational body and to which a plurality of inner teeth are provided at an inner circumference of the inner tooth formation part; a plurality of power transmission bodies that are power-transmissibly disposed between an outer circumferential surface of an outer wheel of the bearing portion and the respective inner teeth of the inner tooth formation part, wherein an engaged portion of the inner tooth moves in a circumferential direction by eccentric rotation of the eccentric rotational shaft; and a maintaining member integrally disposed at a remaining one of the driving rotational body and the driven rotational body, separating respective power transmission bodies, and allowing the respective power transmission bodies to move in a radial direction, wherein a recess portion is formed at at least one of the outer circumference of the eccentric rotational shaft and an inner circumference of the bearing portion, and a pressing member that allows the power transmission body to generate power in a tooth bottom surface direction of the inner tooth through the bearing portion is disposed at the recess portion.