In this paper, the authors present the analysis and design of a small size, low profile and single-band square shape sierpinski fractal antenna. The proposed antenna design, analysis and characterization have been performed using the Method of Moments (MoMs) technique. The use of fractal pattern in this paper provides a simple and efficient method for obtaining the compactness. A square shape sierpinski based fractal antenna is designed for 5.09GHz. The FR-4 epoxy/glass material is used as substrate.