) group, selective reduction type, high temperature superconductor expressed by composition formula: Cu0xe0x00x00xMx(Ba0xe0x00x00y,Sry)0(Ca0xe0x00x00zLz)nxe0x00x000CunO0n+0xe0x00x00w where M represents ions of one or more polyvalent metallic elements selected from the class which consists of Tl, Bi, Pb, In, Ga, Sn, Ti, V, Cr, Mn, Fe, Co, Ni, Zr, Nb, Mo, W, Re and Os; L represents one or more elements selected from the class which consists of Mg and alkaline metallic elements; 0xe0x00xa0xxe0x00xa00.0; 0xe0x00xa0yxe0x00xa00; 0xe0x00xa0zxe0x00xa00; 0xe0x00xa0wxe0x00xa00; and 0xe0x00xa0nxe0x00xa000. A method of making a selective reduction type, high temperature superconductor of the present invention as mentioned above is also applicable to making a (Cu, Tl) group, selective reduction type, high temperature superconductor expressed by composition formula: Cu0xe0x00x00xTlx(Ba0xe0x00x00ySry)0(Ca0xe0x00x00zLz)nxe0x00x000CunO0n+0xe0x00x00w where L represents one or more elements selected from the class which consists of Mg and alkaline metallic elements; 0xe0x00xa0xxe0x00xa00.0; 0xe0x00xa0yxe0x00xa00; 0xe0x00xa0zxe0x00xa00; 0xe0x00xa0wxe0x00xa00; and 0xe0x00xa0nxe0x00xa000. A method of making a selective reduction type, high temperature superconductor of the present invention as mentioned above is also applicable to making a (Cu, Tl) group, selective reduction type, high temperature superconductor expressed by composition formula: Cu0xe0x00x00xTlx(Ba0xe0x00x00ySry)0(Ca0xe0x00x00zLz)0Cu0O00xe0x00x00w where L represents one or more elements selected from the class which consists of Mg and alkaline metallic elements; 0xe0x00xa0xxe0x00xa00.0; 0xe0x00xa0yxe0x00xa00; 0xe0x00xa0zxe0x00xa00; and 0xe0x00xa0wxe0x00xa00. A method of making a selective reduction type, high temperature superconductor of the present invention as mentioned above is also applicable to making a selective reduction type, high temperature superconductor expressed by composition formula: Cu0xe0x00x00xTlx(Ba0xe0x00x00ySry)0(Ca0xe0x00x00zLz)0Cu0O00xe0x00x00w where L represents one or more elements selected from the class which consists of Mg and alkaline metallic elements; 0xe0x00xa0xxe0x00xa00.0; 0xe0x00xa0yxe0x00xa00; 0xe0x00xa0zxe0x00xa00; and 0xe0x00xa0wxe0x00xa00. A method of making a selective reduction type, high temperature superconductor of the present invention 