The Ge₅₀Te₅₀/Zn₁₅Sb₈₅ nanocomposite multilayer films are prepared by the magnetron sputtering. The variation of resistance with temperature and with crystallization activation energy is studied. The multilayer structure of the section before and after the crystallization for Ge₅₀Te₅₀/Zn₁₅Sb₈₅ nanocomposite multilayer film is compared by transmission electron microscope. The phase change memory device based on GT(7nm)/ZS(3nm)₅ is manufactured, and the electrical performance is measured. The fast switching speed, low operating power consumption, and good cycling performance are achieved for Ge₅₀Te₅₀/Zn₁₅Sb₈₅. Ge₅₀Te₅₀/Zn₁₅Sb₈₅, which is a kind of nanocomposite multilayer film, a promising phase change storage material with high thermal stability and low power consumption.