To smoothly carry and store a ceramic substrate sheet by chamfering at least two neighboring corners in the direction of thickness.

A ceramic substrate sheet 10 has a chamfer 15 in the direction of thickness at the chamfered corner 13 and thus the tip end 13 of the chamfered corner does not abut on the substrate receiving part 24a of a carrying rail 24. Since the angle made by a lower main surface 18b and the chamfer 15 is made an obtuse angle, even if the substrate receiving part 24a has depressions and projections 24c, there is no big friction or scratch between the substrate receiving part 24a and the depressions and projections 24c and thus the ceramic substrate sheet 10 can be smoothly carried. The chamfer 15 may be formed by grinding by a grindstone or by cutting by a sharp cutter like a razor before burning a green sheet laminate.