When make multi-layer ceramics device such as EMI filter, there are a lot of process problems. Specially, crack, camber and delamination should be controlled surely by different sinter shrinkage rate of interface of two materials. The purpose of this work was to co-fire defectfree ferrite/varistor ceramic multi-layers fabricated via a calcination temperature and organic vehicle contents of ferrite. Sintering shrinkage of both calcined ferrite and varistor materials were measured using dilatometer. X-ray diffraction analysis indicated that no significant phase change occurred in the materials under investigation as a result of the sintering process. Crack and delamination of each interface were observed by scanning electron microscopy and optical microscope. We obtained the defect-free and co-fired ferrite/varistor ceramic multi-layer by controlling calcinations temperature.