A dielectric ceramic composition consisting essentially of a solid solution of a main component of a ternary system Pb(Ni.sub.1/3 Nb.sub.2/3)O.sub.3 -Pb(Zn.sub.1/3 Nb.sub.2/3)O.sub.3 -Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3, and additional components composed of PbTiO.sub.3 and a complex perovskite compound of the general formula: A(Mn.sub.1/2 Nb.sub.1/2)O.sub.3 (wherein A is at least one element selected from the group consisting of Pb, Ba, Sr and Ca). The composition may further contain as an additional components, a complex perovskite compound expressed by the general formula: B(Cu.sub.1/2 W.sub.1/2)O.sub.3 wherein B is at least one element selected from the group consisting of Pb, Ba, Sr and Ca. The main component consisting essentially of 66.53 to 67.27 Wt % of Pb.sub.3 O.sub.4, 25.79 to 26.08 wt % of Nb.sub.2 O.sub.5, 1.47 to 5.09 wt % of NiO, 2.00 to 5.49 wt % of ZnO and 0.02 to 1.19 wt % of MgO and having a composition expressed by the general formula:xPb(Ni.sub.1/3 Nb.sub.2/3)O.sub.3 -yPb(Zn.sub.1/3 Nb.sub.2/3)O.sub.3 -zPb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3(wherein x, y and z are percentages by weight of the respective three components and have the following values: 20.0.ltoreq.x.ltoreq.70. 0, 25.0.ltoreq.y.ltoreq.69.5, and 0.5.ltoreq.z.ltoreq.30.0). The contents of the respective additional components per 100 parts by weight of the main component are, 0.5 tp 7.0 parts by weight for PbTiO.sub.3, 0.1 to 5.0 parts by weight for A(Mn.sub.1/2 Nb.sub.1/2)O.sub.3, not more than 5.0 parts by weight for B(Cu.sub.1/2 W.sub.1/2)O.sub.3, respectively.