In this work, an optimization method of a six - bars mechanism is proposed, which is formulated with natural coordinates easing the kinematic modeling, since it avoids use of transcendental functions. After the kinematic model is established, the optimization problem is formulated to be solved by using a genetic algorithm with real or continuous coding; thus, avoiding computation of highly complex derivatives. The relevance of this work lies on fact that an alternative method is offered to those dependent on angular parameters, where equations that model the mechanism, are complicated, even in the simplest mechanism.