A three-dimensional micromechanical model was developed to investigate the load deformation characteristics of cord-rubber composites. A finite-element model that integrates a solid rubber element and a twisted cord element which takes into account coupling effects of various deformations is developed to investigate the influence of cord shape on the load-deformation characteristics. The finite-element model developed was validated by comparing the results with those from a solid three-dimensional finite-element analysis. Numerical results of deformations and stress distributions are presented to illustrate the influence of cord shape, cord-rubber anisotropy, and rubber thickness. The results presented illustrate that cord shape and rubber thickness surrounding the cord have a strong effect on the values of deformations and interface stress distributions.