Herein disclosed is a reclining device of an automotive seat. The device comprises substantially identical two units which are spaced from each other, each unit having an operation handle for achieving an angular position adjustment of a seatback relative to a seat cushion. An elongate rod extends between the operation handles to effect synchronous pivotal movements of the same. A resilient block constructed of polyurethane foam, sponge rubber or the like is disposed between the rod and a part of the seat cushion to suppress vibration of the rod.