To provide a ceramic substrate to be divided certainly at the time of division without the risk of cracking along the recess part for division at the time of forming elements on the ceramic substrate having a recess part for division or during conveyance between steps.

A ceramic substrate having a recess part for division is formed such that the maximum thickness T of a ceramic molten layer 4a in the surface layer part of a plurality of recess parts for division 4 provided in rows on one of the principal planes 2 of the ceramic substrate 1 is 10 μm or less, the depth D of the recess parts for division 4 is 10-25% with respect to the thickness t of the ceramic substrate 1, and the pitch P between the recess parts for division 4 is 60-130 μm.