Recently, stable junctions can be directly synthesized through a floating catalyst CVD technique to link the carbon nanotubes into a reticular netwrok named reticular carbon nanotube (r-CNT).An r-CNT composite can be fabricated by insert a polymer into the r-CNT which overcomes the inherent disadvantages of the lack of weaving of the CNTs and the low strength of the interface between CNTs and the polymer.In this paper, a plain strain model of the r-CNT composite is proposed and large tensile and shear strains 50% are applied on the boundaries of the model to investigate its deformation mechanism and mechanical behaviours under large deformation.The calculation are performed by a two-scale expansion method extended by large deformation equations.