Turbomachines, specifically centrifugal pumps, are rotodynamic machines and their use is to pump liquids. In this paper, the design of the rotor of these centrifugal pumps is developed for laminar and incompressible fluids in two dimensions using the method of finite element and topology optimization method based on gradient. A code in MATLAB has been developed for the solution of Navier Stokes equations using the finite element method (FEM) and the method of moving asymptotes (MMA) for the minimization of a bi-objective function (energy dissipation and vorticity). The topology result obtained in the minimization of this bi-objective function (w <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</inf> = 0.8 and w <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">r</inf> = 0.2), corresponds to the standard geometry of the rotors of centrifugal pumps in traditional working conditions. The performance obtained in this minimization was 5.94 [Watts] with a fraction volume in the whole domain of 0.248. In conclusion, mathematical optimization tools can help engineering designers to obtain non-intuitive designs and improve their results.