This letter presents a recursive technique to synthesize the array factor (AF) of a concentric ring array. In this method, first, the problem is modeled using the traditional least square method (LSM). In the second step, a recursive technique is applied to the defined problem. It is shown that for many practical ring arrays, only a few iteration number is sufficient to obtain a solution with high accuracy. To evaluate the performance and benefits of the proposed method, various concentric ring arrays with different array factor, including equi-ripple pattern, pattern with deep nulls, flat-top array factor, are examined. It is shown that the introduced procedure is a very noble candidate for this purpose.