Abstract: Cubic conductive copper oxide ceramics which are represented by the following formula I:(M.sub.x Cu.sub.y).sub.7 O.sub.z A.sub.w Iwherein M represents at least one element selected from the group consisting of In, Sc, Y, Tl, and Ga, A represents Cl, NO.sub.3, or Cl and NO.sub.3, x+Y is a value of 1, x/y is a number of 0 to 10, z is a number of from 6 to 8, and w is a number of from 1 to 9, and processes for producing same by mixing at least one nitrate and/or chloride of a metal selected from the group consisting of In, Sc, Y, Tl, and Ga, with copper nitrate and/or copper chloride, and firing the mixture at from 200.degree. to 600.degree. C. The copper oxide ceramics are preferably used as electrodes in various fields, heat emiters and also as a material for producing superconductors.