The invention provides conductive metallized nickle-plated or silver-plated glass fiber, glass cloth and a preparation method thereof. The conductive metallized nickle-plated or silver-plated glass fiber comprises a glass core material and a metal network surface layer wrapping on the glass core material, wherein the metal network surface layer contains nickle metal or silver metal; the glass core material contains 30-40% of Co2O3 or MnO2. The shielding frequency bandwidth of the conductive metallized nickle-plated or silver-plated glass material is 3MHz-40GHz, and the shielding attenuation value thereof is 85dB-90dB. The glass material does not burn under the burning environment with the temperature of 700 DEG C, does not melt at the temperature of 800 DEG C, and can be used for making fire-fighting clothes, chemical clothes, live line work and nuclear power clothes and protecting the special environment of a steel plant. In addition, the conductive metallized nickle-plated or silver-plated glass fiber, the glass cloth and the preparation method are also used for high-temperature-resistant control cable wave-preventing sleeves in chemical industry and smelting, directional petroleum-producing cable wave-preventing sleeves and high-speed engine control cable wave-preventing sleeves.