A rounding device for rounding food dough is provided with a conveyance device (9) which conveys the food dough (7) and a pair of forming plates (11, 13), which, on the upper face of the conveyance device (9), are arranged so as to extend along the conveyance direction (R) of the conveyance device (9). The forming plates (11, 13) at least opposed sloped surfaces (18B, 22B). The sloped surfaces are tilted outward from the lower side to the upper side so that the gap between the sloped surfaces is narrow on the lower side and wide on the upper side. The rounding device rounds the food dough using the sloped surfaces (18B, 22B) of the pair of the forming plates (11, 13). The pair of the forming plates (11, 13) has longitudinal components which move longitudinal relative to each other in the opposite directions, and the pair of forming plates (11, 13) also has a lateral component which move relative to each other in the width direction perpendicular to the longitudinal direction so as to approach and separate from each other. The pair of forming palates (11, 13) can move along a movement path in which the distance of movement according to longitudinal components is greater that the distance of movement according to the lateral component.