To provide a raw material fiber feeder constituted so as to prevent weight unevenness without decreasing spun amount.

In a raw material fiber feeder of a carding machine having a push plate 5 reciprocatingly moving between a push feed starting position and a push feed finishing position so as to push and feed a raw material fiber intermittently charged from a weighing hopper 4 toward a feed roller 1 quantitatively and continuously feeding the raw material fiber to the carding means, plural spikes 6 arranged in the direction along the push plate 5 are liftably provided so as to regulate that raw material fiber mass which stays on this side of the feed roller 1 displaces to the push plate side 5 following return from a push feed finishing position of the push plate 5 to the push feed starting position and the spike is lifted and lowered in interlock with the push plate 5 by an air cylinder 7.