A method of fabricating a ceramic multilayer substrate includes steps of laminating a plurality of green sheets including an inside green sheet formed with a conductor pattern and pressing a laminate of green sheets under a predetermined pressure together with sheet restricting members applied to opposite surfaces of the laminate respectively, thereby bonding the laminate and sheet restricting members together, each sheet restricting member having a smaller percent change in thickness than the green sheets during the bonding and a higher firing temperature than the green sheets, firing a bonded assemblage of the green sheets and sheet restricting members at a firing temperature of the green sheets, and removing the sheet restricting members from the opposite surfaces of a fired body.