Abstract: With epoxy resins cured by different curing agents as the matrix, hollow glass beads (HGB) as the dispersed phase, and silane coupling agents as the additive, solid buoyancy materials were prepared. The effects of additive contents of silane coupling agents on water absorption and compression strength of the solid buoyancy materials before and after water absorbing under the condition of hydrostatic pressure of 45 MPa and after drying were studied. The differences in the properties of the two curing system solid buoyancy materials were discussed. The results show that adding 6% (mass fraction) coupling agents could improve the water absorption and compression strength of the solid buoyancy materials. The compression strength of the solid buoyancy material cured by acid anhydride curing agent MeTHPA was higher than that of the solid buoyancy material cured by amine curing agent DDM. The compression strength of the solid buoyancy materials decreased in varying degrees after water absorbing under the condition of hydrostatic pressure of 45 MPa and after drying, and adding coupling agents could reduce the decrease of compression strength.