A metering feeder formed by inner and outer cylinders sharing a center line, having a gap (t) between a bottom plate of the outer cylinder and a lower end of the inner cylinder, an annular transport space for a powder/granular material being provided between the inner and outer cylinders (1,2), an outer rotating ring provided along an inner periphery of the outer cylinder being connected to a tip end of a central rotating blade provided on an upright rotating shaft projected at a center part of the bottom plate, a plurality of outer rotating blades directed toward an inside being provided on the outer rotating ring, a rotating disc having an upper surface on the same plane as an upper surface of the bottom plate being provided, a powder/granular-material discharge groove concentric with the disc being formed on the upper surface of the rotating disc, the powder/granular-material discharge groove supporting the rotating disc on a support machine frame so that it is disposed over an inside and outside of the outer cylinder, the powder/granular material in the annular transport space being metered by the outer rotating blade and supplied to the powder/granular-material discharge groove by rotating the central rotating blade and the rotating disc in the same direction, and the powder/granular material being transported to an outside of the outer cylinder by the powder/granular-material discharge groove, the metering feeder is characterized in that: a discharge opening is provided in the support machine frame on an outer side of the rotating disc outside the outer cylinder, and in the powder/granular-material discharge groove of the rotating disc, a vertically-movable scraper for large supply, fitted with the powder/granular-material discharge groove for blocking the powder/granular material in the powder/granular-material discharge groove and for guiding it to the discharge opening and a fixed small scraper for small supply and for blocking a part of the powder/granular material in the discharge groove on a downstream side of the vertically-movable scraper and guiding it to the discharge opening are provided; and the vertically-movable scraper is made capable of elevating between a lowered position fitted in the powder/granular-material discharge groove and a raised position away from the powder/granular-material discharge groove by elevating driving means. a discharge opening is provided in the support machine frame on an outer side of the rotating disc outside the outer cylinder, and in the powder/granular-material discharge groove of the rotating disc, a vertically-movable scraper for large supply, fitted with the powder/granular-material discharge groove for blocking the powder/granular material in the powder/granular-material discharge groove and for guiding it to the discharge opening and a fixed small scraper for small supply and for blocking a part of the powder/granular material in the discharge groove on a downstream side of the vertically-movable scraper and guiding it to the discharge opening are provided; and the vertically-movable scraper is made capable of elevating between a lowered position fitted in the powder/granular-material discharge groove and a raised position away from the powder/granular-material discharge groove by elevating driving means.