We proposed a method to enhance the gain of a truss reflector antenna by optimizing the placement of a minimal number of tension ties. To analyze the impact of tension tie placement on antenna performance, the bore-sight gain was compared by adjusting the length of each subdivision ln. The bore-sight gain of the optimized reflector antenna was then compared with those of two conventional truss reflector models (N sub = 4 and 5). The optimized model, which utilized the same number of tension ties as the conventional design with Nsub = 4, achieved a 0.6 dB improvement in bore-sight gain. Subsequently, the optimized antenna obtained a bore-sight gain comparable to that of the reflector with 30 additional tension ties. These results demonstrated that the proposed optimization method can design reflector antenna with high gain characteristic while reducing the number of tension ties.