A multilayer ceramic electronic device comprising a lamination in which an internal electrode layer 3 and a dielectric layer 2 are laminated alternatively, wherein the dielectric layer 2 is comprised of a dielectric ceramic composition including a main component represented by a general formula of ABO3 and a rare-earth component R, and segregation phases 5 including the rare-earth component R are present in the dielectric layer 2. When the dielectric layer 2 is separated to six areas by dividing the dielectric layer 2 sandwiched by a pair of the internal dielectric layers 3 in the thickness direction, there are the R segregation phases present in two neighboring areas 2a respectively adjacent to the pair of the internal electrode layers 3 in the dielectric layer 3 at a ratio of double or more compared with the R segregation phases present in two central areas 2b located at a substantially center in the dielectric layer 2.