Meta-materials are usually metal-dielectric composites having unique electromagnetic properties. These unique electromagnetic properties of meta-materials have attracted much interest. Therefore, meta-material fabrication is developing, The fabrication method is based on the design of polymer material with holes. Where these holes are filled with metal in a micro-structure form which produce the meta-materials. Themethod for design this structure includes arrays of wires, which allow the permittivity to be tuned through the details of the wire diameter and spacing. Metamaterials are characterized by many parameters, one of them is its ability to control electromagnetic waves in the subwavelength, depending on the resonant unit cells.This work is done by using a simulation program to draw a metamaterials in the form of 2D array of wires as a fiber. Then simulate the effective mode index inside them. our results show that the effective mode index is increased by increasing the plasma frequency.