A kind of leadfree glass powders based on Bi2O3B2O3ZnOBaOCuO system was prepared in this paper for the performance requirements of microelectromechanical system (MEMS) sealing glass. The effects of Bi2O3/B2O3 ratio （n(Bi2O3)/n(B2O3)） and βeucryptite powder content on the network structure, thermal properties, sealing temperature and sintered micromorphology of MEMS sealing glass were separately studied by Raman spectra, XRD, coefficient of thermal expansion (CTE), sintering image and SEM. The results show that the content of [BiO3] and [BiO6] increases with the increase of n(Bi2O3)/n(B2O3), while the transition from [BO4] tetrahedron to [BO3] triangulation leads to the glass network connection strength weak and structure loose. With the increase of n(Bi2O3)/n(B2O3), the CTE of the glass increases while the characteristic temperature and sealing temperature decrease gradually, but later change slowed. The CTE of the composite glass decreases obviously while the characteristic temperature and sealing temperature change little with the increase of βeucryptite powder content, at the same time the fluidity of the composite glass powder becomes worse.