Nowadays, the market trends on engine components development are focused in lower emissions, fuel consumption reduction, downsizing and higher peak combustion pressure. In this scenario, macro-profile bearing optimization plays an important rule on stresses reduction and consequently structural safety factor increasing. Thus, a structural optimization was performed to define the best crankpin profile for a given crankshaft (named U-Shape crankpin profile). This profile can be designed with emphasis on mass and friction reduction without penalties on structural and torsional stiffness results. Since there is more than one objective, it is necessary to perform a multi objective optimization that will result in a Paretto frontier, in which all design points meet the targets. All in all, target of this work is to study the optimization step considered to define the U-Shape profile for a given crankshaft, especially the genetic algorithm (NSGA-II) as well as the benefits of the optimized macro-profile.