Provided is a chain power transmission mechanism and a silent chain each having a simple configuration, easy to manufacture, and capable of reducing noise in the entire chain power transmission mechanism. Link plates of the silent chain include an inner-flank-engagement link plate which engages with a sprocket in an inner flank engagement mode and an outer-flank-engagement link plate which engages with the sprocket in an outer flank engagement mode. The inner-flank-engagement link plate and the outer-flank-engagement link plate are arranged such that combinations of the link plates at positions where engagement with and disengagement from a plurality of the sprockets are synchronized include a combination in which at least one of the link plates is different in engagement mode from another link plate.