Morphing aircraft require the airfoil camber to change continuously and smoothly. The flexible skins must have substantial in-plane expansion deformability, while at the same time it must be able to bear the out-of-plane aerodynamic loads. In this article, a new flexible honeycomb structure is designed for the wing with a variable camber trailing edge. The relationship between the in-plane deformability and the shape parameters of the flexible honeycomb are studied. Simulation and experimental studies are carried out for the flexible honeycomb. The results show that the flexible honeycomb has substantial in-plane deformability and maintains good out-of-plane bearing capacity, which satisfies the application requirements of the wing with a variable camber trailing edge.