To provide an IC card, which secures satisfied flatness of the card
surface to achieve good printing properties on the card surface. An IC
card has a core layer which includes a plurality of sheet materials
wherein inner core sheets adjacent to an IC module have through holes
formed in a region corresponding to the IC mounted portion, wherein a
relationship A=(B1+C1).+-.30 .mu.m is satisfied, where A (.mu.m)
represents the sum of heights of the through holes, B1 represents a
projection height on an IC mounted surface of the IC module, and C1
represents a projection height on an IC non-mounted surface. By virtue of
having this structure, the IC card can secure card flatness sufficient to
obtain satisfied printing properties with respect to the rewrite sheet.