In order to provide the theoretical basis for the process and performance optimization of nano-ZnO/ethylene-vinyl acetate copolymer (EVA) composites, nano-ZnO/EVA composites were prepared by melt blending method. The melting and crystallization behaviors of the composites were studied by DSC. The influence of the mass fraction and surface-modification by coupling agent of nano-ZnO on dynamic rheological behavior of the composite system was analyzed by rotational rheometer. The results show that both of the crystallization temperature and melting temperature of nano-ZnO/EVA composites increase firstly, and then decrease with the nano-ZnO mass fraction increasing, while the modified nano-ZnO mass fraction has little effect on melting temperature and crystallization temperature of modified nano-ZnO/EVA composites. The complex viscosity of nano-ZnO/EVA system changes suddenly when the mass fraction of nano-ZnO is greater than 20%, and the storage modulus-angular frequency curve shows the second plateau at low frequency region which corresponding to the two section of linear viscoelastic regions at strain scanning curves, and indicate that local ordered percolation network structure is formed due to the correlation, glomeration between nano-ZnO particles and the interaction between particles and matrix. While after the surface-modification of nano-ZnO by coupling agent, the complex viscosity of system decreases and the plateau of storage modulus-angular frequency curve does not appear, which indicates that the modified nano-ZnO particles are dispersed more homogeneously in the composite system. The research shows that surface-modification of nano-ZnO by coupling agent improves the dispersibility of nano-ZnO in EVA.