Most power applications today rely on copper wire to conduct electricity. However, with the rapid progress of HTS technology in the last decade, superconducting wire promises to become a viable copper alternative for advanced power systems. HTS wire carries more than one hundred times the current of an equivalent size of copper wire and also has zero resistance to direct current electricity. These attributes can translate into significant reductions of cost, size and weight for motors, generators, and power cables. This book is a practical work to prepared High Temperature Superconductor Bi2-xHgxSr2-yBayCaCu2O8 and Bi 2-xHgxSr2-yBayCa2Cu3O10 compounds were prepared with (0 ,0.05 ,0.1 ) Hg and Ba substation instead of Bi and Sr respectively by solid state reaction and then ground to fine powder of about ( 0.3 and 0.4)μm average particle size using Powder In Tube Method(PIT).