The invention provides a ceramic electronic device that includes: a ceramic main body having at least two edge faces facing each other; and external electrodes formed on the two edge faces, wherein: the external electrodes have a structure in which a plated layer is formed on a ground layer having ceramic; a main component of the ground layer is a metal; the external electrodes have an extension region that extends to at least one of four side faces from the two edge faces of the ceramic main body; a part of the extension region corresponding to a corner portion of the ceramic main body has afirst portion having a maximum spaced distance of 10 [mu]m or less in a face direction of the ground layer; and the plated layer has an average thickness that is 30% or more with respect to the maximum spaced distance, and covers the first portion.