In this paper, we analyze the limitations that impose the presence of uncertainty in the design of optimal energy management strategies (EMSs) for fuel cell (FC) hybrid electric vehicles. Using an electric powertrain constituted by a hydrogen FC and a battery bank, the fuel consumption minimization problem is analyzed in the presence of parametric uncertainty. The conditions that ensure that the nominal optimization problem matches the solution of the real (unknown) optimization problem are clearly stated. By observing that the uncertainty will limit the feasible solutions of the minimization consumption problem, supervisory control constituted by heuristic rules is proposed to face such limitations, resulting in a mixed optimal–heuristic EMS. The effect of the powertrain design, driving cycle, and initial conditions in the proposed strategy is discussed. Numerical simulations provide evidence of the advantages and features of the supervisory control strategy.