Suspension systems used in vehicles are an important factor affecting comfort, safety, and vehicle performance. These systems are effective in the vehicle's total weight and fuel consumption. However, while lightening the weight, it should also be ensured that the strength is within safe limits. For this purpose, dual-phase (DP) and complex-phase (CP) steel materials were used. In the study, the topology optimization of the front lower suspension arm, designed for a light commercial vehicle, was carried out with the finite element method. As a result of the topology optimization, the weight was reduced by 7.5% compared to the current design, while maintaining the safe strength values. This result will significantly contribute to reducing material costs by using dual-phase (DP) and complex-phase (CP) steel materials, reducing exhaust emissions by lightening vehicle weight, and developing more sustainable designs.