To meet the urgent demand of low-density adhesives in next-generation satellite structural platforms，this study employed a silane coupling agent to surface-modify hollow glass microspheres.A low-density adhesive was prepared using a blending method，followed by testing of mechanical properties，space environment resistance，pull-out strength of embedded anchors in honeycomb sandwich structures，and adhesive density.The results show that the new low-density adhesive has a density of 0.67 g/cm³，46% lower than that of the J-133 adhesive，a shear strength of 26.2 MPa，and a pull-out force of 5.1 kN for M4 potted inserts in honeycomb sandwich panels.After high/low-temperature thermal shock testing，the mechanical properties changed little，and both the total mass loss（TML）and collected volatile condensable materials（CVCM）are reduced compared with J-133.The adhesive thus exhibits excellent mechanical performance and space-environmental resistance，and can meet the requirements of future spacecraft for low-density adhesives.