A ceramic electronic device includes a multilayer chip including a multilayer structure, a first cover layer and a second cover layer and having a parallelepiped shape, the multilayer structure having a structure in which each of a plurality of dielectric layers and each of a plurality of internal electrode layers are alternately stacked and are alternately exposed to a first end face and a second end face of the multilayer chip, the first end face being opposite to the second end face, the first cover layer being provided on an upper face of the multilayer structure in a stacking direction, the second cover layer being provided on a lower face of the multilayer structure, a first external electrode formed on the first end face, and a second external electrode formed on the second end face. In this structure, a relationship of 0.20≤R1/√{square root over ( )}(P12−C12)≤0.80 is satisfied.