In this paper, the authors present design of microstrip patch antenna at 2.4GHz. Further by introducing fractal concept to the star-shaped microstrip antenna Koch curve antenna is designed. The Koch island fractal patch antenna is introduced in order to reduce the antenna size. By space-filling property of fractal geometry, this antenna reveals lower resonant frequency. Based on experimental result, it is found that as iteration and iteration factor increases, the resonant frequency of this patch antenna decreases. Broad band operation with size reduction is obtained.