To provide a vice for a round bar, and a work receiving base which are high in accuracy of the fixing position, capable of easily adaptable to the change in the diameter of a work, and capable of fixing a plurality of works in a correct positional relationship.

One surface 13 of work holding surfaces 13, 23 of two mouth pieces opposite to each other is a surface orthogonal to a receiving surface 35, and the other surface 23 is a surface inclined toward the receiving surface 35. A work receiving base is provided with a slide base 31 and an intermediate mouth piece 33 provided with two work holding surfaces 13, 23 which are the surfaces where at least one surface 23 projected on the slide base is inclined to the slide base side, and the slide base 31 is provided with the receiving surface 35 extending to the inclined work holding surface side. Since one work holding surface 232 is inclined to the receiving surface 35 side, a work 60 is pressed against the receiving surface 35 side, and since one work holding surface 13 is orthogonal to the receiving surface 35, the fixing position of the work 60 can be correctly specified with these surfaces as a reference.