PURPOSE: To provide a ceramic package aggregate, on which a large quantity of burrs are never generated and in which a break is never generated, and a method of splitting the aggregate.

CONSTITUTION: A plurality of independent package parts 12, 14, 16 and 18 are formed on a sheetlike laminated ceramic board 10, dividing grooves, consisting of surface side groove 20a cut from the side of the surface mounted with an element, and rear side groove 20b cut from side of the rear of the board 10 are formed on the boundary parts 20 between the parts 12, 14, 16 and 18 and the groove depth of the grooves 20b is formed in such a way that it is deeper than that of the grooves 20a. By applying such a force as to extend the grooves 20a in the boundary parts 20, the parts 20 are broken and the board 10 is split into the individual package parts 12, 14, 16 and 18.