Two 3D-sandwiched structure reinforced composites were separately prepared by cyanate ester/ phenolic resins with fabric hollow matrix. The mechanical and dielectric properties of composites are performed. The results indicate that compressive strength of the composites is respectively 5. 0 and 3. 5 MPa on cyanate ester or phenolic resins. Compared with traditional corn materials such as honeycomb and foam, the mechanical strength is increased significantly. The dielectric constants are 1. 5 and 1. 6 by different resins, besides the constants are stabilized on varied frequency.