A ceramic electronic device includes a multilayer structure in which each of a plurality of dielectric layers and each of a plurality of internal electrode layers are alternately stacked. A main component of the plurality of dielectric layers is a ceramic having a perovskite structure of which an A site includes at least Ba and of which an A/B ratio is 0.980 or less. The plurality of internal electrode layers include a co-material. A total amount of Ti, Zr and Hf is 90 mol % or more in metal elements included in the co-material and an amount of Ba is 10 mol % or less in the metal elements.