AC losses were estimated on large current capacity cable conductors on the assumption that current was distributed to each layer uniformly. The estimation clarified wire characteristics and structure for a required large capacity and small loss conductor. From the point of those researches on conductor design, the honeycomb partition structure was chosen. We adapted evacuated extrusion method to making ceramic partition and found 31 A of critical current and 3800 A/cm 2 of engineering current density in a calcium carbonate partitioned seven-core wire. AC losses of a strontium carbonate partitioned nineteen-core wire were evaluated. In parallel field, which is a main component in multi-layered cable conductor, some loss reduction was found. The AC losses were also found evident advantages in perpendicular field.