Electromagnetic properties of single-layer silver nano-particles of compound metamaterials are theoretically analyzed. MATLAB numerical calculation and CST simulation are used to verify the theory. The results show numerical and simulated results of 4.75 nm nano-silver arrays are basically the same, and there are Lorentz resonance. The simulated results have redshift compared to numerical results, having a weak magnetic resonance. Further simulated compounded by the use of 4.75 nm spherical to form large particles of 100 nm, the results show that there are negative real permittivity and negative real effective permeability and negative refractive index in the 300~380 THz range. That means 100 nm composite spherical particles have a strong magnetic resonance effect and consistent with the theoretical analysis.