A silent chain (1 1 , 1 2 ), comprising: inner link plates each having a pair of teeth , a pair of pin holes , and a back face curved convexly, the inner link plates being arrayed in widthwise and longitudinal directions of the chain; guide link plates each having a pair of pin holes and abut portions formed on a back face thereof at positions corresponding to the pin holes , the guide link plates being disposed at both outer sides of the inner link plates arrayed in the width direction; and pins retained by the pin holes of the guide link plates and inserted through the pin holes of the inner link plates such that the inner link plates adjacent in the longitudinal direction are articulably and endlessly connected; wherein a length (Hi) from a line (L-L) connecting centers of the pin holes to a convex apex portion of the back face of each inner link plate is substantially equal to a length (Hg) from the line (L-L) to the apex portions of the abut portions of each guide link plate , the convex apex portion of each inner link plate is formed at a center between the pair of pin holes , and the convex apex portions of the inner link plates are formed per every pitch (P) which is a distance between the pair of pin holes, and the apex portions of the abut portions of the guide link plates are formed per every pitch at a center between the adjacent convex apex portions , characterized in that each guide link plate is of a low rigidity type plate including: a crotch portion formed on the back face at a center between the pin holes ; and ear portions formed on both sides in the longitudinal direction of the crotch portion and being the abut portions. inner link plates each having a pair of teeth , a pair of pin holes , and a back face curved convexly, the inner link plates being arrayed in widthwise and longitudinal directions of the chain; guide link plates each having a pair of pin holes and abut portions formed on a back face thereof at positions corresponding to the pin holes , the guide link plates being disposed at both outer sides of the inner link plates arrayed in the width direction; and pins retained by the pin holes of the guide link plates and inserted through the pin holes of the inner link plates such that the inner link plates adjacent in the longitudinal direction are articulably and endlessly connected; wherein a length (Hi) from a line (L-L) connecting centers of the pin holes to a convex apex portion of the back face of each inner link plate is substantially equal to a length (Hg) from the line (L-L) to the apex portions of the abut portions of each guide link plate , the convex apex portion of each inner link plate is formed at a center between the pair of pin holes , and the convex apex portions of the inner link plates are formed per every pitch (P) which is a distance between the pair of pin holes, and the apex portions of the abut portions of the guide link plates are formed per every pitch at a center between the adjacent convex apex portions , characterized in that each guide link plate is of a low rigidity type plate including: a crotch portion formed on the back face at a center between the pin holes ; and ear portions formed on both sides in the longitudinal direction of the crotch portion and being the abut portions. a crotch portion formed on the back face at a center between the pin holes ; and ear portions formed on both sides in the longitudinal direction of the crotch portion and being the abut portions. <EOS>