Aiming at the performance requirements of vacuum glass sealing, a bismuth-based amorphous lead-free glass powder for vacuum glass sealing was prepared by high temperature melting method. The effects of m(ZnO)/m(B2O3) mass ratio on network structure, characteristic temperature, coefficient of thermal expansion and sealing temperature of Bi2O3-B2O3-ZnO glass were studied by high temperature X-ray diffraction, powder X-ray diffraction, Raman spectroscopy, differential scanning calorimeter, thermal expansion test and scanning electron microscope. The results show that increasing m(ZnO)/m(B2O3) mass ratio can promote the transformation of zinc-oxygen polyhedron from ［ZnO4］ to ［ZnO6］, resulting in a decrease in the coefficient of thermal expansion and an increase in the characteristic temperature. When m(Bi2O3)∶m(B2O3)∶m(ZnO) mass ratio is 80∶7∶13, the glass has lower glass transition temperature Tg (371 ℃) and expansion softening temperature Tf (401 ℃), the coefficient of thermal expansion is 9.3×10-6 ℃-1, and the sealing temperature is 450 ℃, which can meet the requirements of vacuum glass sealing for low melting point sealing glass powder.