Abstract: A multi-layer ceramic substrate having an in-plane shrinkage ratio of 1% or less with 0.1% or less of unevenness, inorganic particles remaining on the external electrodes being 20% or less by mass as a percentage of one or more metals constituting inorganic particles per the total amount of one or more metals constituting the external electrodes and one or more metals constituting the inorganic particles, is produced by (a) preparing a slurry containing ceramic material powder and an organic binder to form low-temperature-sinterable green substrate sheets, (b) laminating the green substrate sheets after forming electrodes thereon, to produce an unsintered multi-layer ceramic substrate, (c) bonding a constraining layer comprising inorganic particles, which are not sintered at the sintering temperature of the unsintered multi-layer ceramic substrate and have an average particle size of 0.3 ?m or more, 0.