This letter describes a method of withdrawing interdigital electrodes for sidelobe reduction of surface acoustic wave filters by using implicit enumeration algorithm for 0-1 type integer optimization. Obtained results, for example, show that the sidelobe level of 40.98 dB can be obtained by withdrawing 14 electrodes from each of the input and output transducers consisting of 51 electrode pairs. Since the implicit enumeration algorithm gives several sub-optimal solutions in addition to the optimal one, it may be useful for some practical filter design.