Ceramic electronic device and manufacturing method of ceramic electronic device

A ceramic electronic device includes: a ceramic main body of a parallelepiped shape having at least two edge faces facing each other, and having an internal electrode layer inside; and external electrodes formed on the two edge faces and having a structure in which a plated layer is formed on a ground layer having a metal, as a main component, and ceramic; the external electrodes have an extension region which extends to at least one of four side faces from the two edge faces, and a part of which corresponds to a corner portion of the ceramic main body and includes a portion with the ground layer and a first portion, without the ground layer, arranged at a position where one of the two end faces and one of the four side faces are connected; and the plated layer covers the ground layer and the first portion.