Abstract: A modified iterative Fourier technique (IFT) is proposed for disadvantage of numerous elements truncated in the thinned planar arrays synthesis of standard IFT. The method initialized form filled arrays and decreased several elements step by step to avoid running into local optimization. Then the modified IFT is applied to design a low side lobe hexagonal planar array by thinning process. Virtual elements are added in the array for translating the array to rectangle for calculating the array factor of hexagon conveniently. The simulated results show that the performance of the hexagonal planar array is better comparing with using genetic algorithm, and also has the advantage of less computation and high speed.