Paulownia wood was drilled with some glass fibers fulfilled in the holes, which could be the core of the sandwich structures. In the manufacture processing, the fibers and resins left in the holes formed composite columns and merged with the facesheets. These could enhance the mechanical behavior of paulownia wood sandwich structures. Double cantilever beam(DCB) tests and bending analysis with finite element method were carried out. The improvement from the composite columns gave little contribution to bending behavior, but significant contribution to interfacial properties.