With sufficient investigating the effect of pre-oxidation, sealing temperature and holding time on the shear strength and microstructure of the Al2O3-Nb sealing materials. The shear strength, microstructure and element distribution of sealing material were investigated by the strength machine, scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Furthermore, the X-ray diffraction (XRD) was used to investigate the phase of sealing region. The strength results showed that the shear strength reached to 94.5 MPa when the sealing temperature was 1390 ℃ and holding 10 min, the XRD results showed that the Dy2Si2O7 phase was found in the sealant/Al2O3 interface. In addition, the thickness of reaction layer which was formed near the interface of sealant/Al2O3 was about 2 μm