A vaned diffuser provided on a downstream side of an impeller of a centrifugal compressor. The vaned diffuser includes: a diffuser passage forming portion having a hub-side surface and a shroud-side surface and forming an annular diffuser passage on a downstream side of the impeller; and a plurality of diffuser vanes provided in the diffuser passage at intervals in a circumferential direction of the impeller. A fillet is formed in a connection portion between each of the diffuser vanes and at least one of the hub-side surface and the shroud-side surface. Also, where R is a radius of the fillet and b is a vane height of each of the diffuser vanes, and a maximum value of R/b on a downstream side of a throat position of the diffuser passage is larger than a maximum value of R/b on an upstream side of the throat position of the diffuser passage.