This paper aims to develop an analytical design approach of discrete flux weakening (FW) controller that is implemented for high-speed starter/generator systems. The FW control plant has also been derived for small signal analysis while taking into account realistic signal delay effects. Accordingly, a proposed discrete FW controller has been presented. A generalized methodology to select the controller’s gains has been developed in order to guarantee the stability and dynamic performance throughout the whole operating conditions in starter and generator modes. Simulations have been carried out in order to validate the analytical findings and to validate the proposed design.