Lightweight design can be used to save resources and reduce greenhouse gas emissions. One way to implement lightweight design is to use short-fiber reinforced thermoplastic (FRP)-metal-hybrids, which combine the advantages of metal and FRP. These can be produced with injection molding by inserting a metal insert into the cavity of an injection molding machine and then over molding it with FRP. However, there is currently a lack of optimization methods to support product developers in the design synthesis of such hybrids. For this reason, a method for the topology optimization of FRP-metal-hybrids is developed, which aims to increase the pull-out force of the metal insert from the surrounding FRP without damaging the adhesive bond. A weight reduction of the metal insert of such a hybrid structure is prescribed. To ensure that no cavities are created between the FRP and the metal within a sensitivity-based topology optimization, e.g. in Tosca, the method includes an iterative interruption of the topology optimization. The FRP is adapted to the changed structure of the metal insert and the contact pairs between metal and FRP are adjusted. Depending on the structure of the metal insert, the flow paths of the FRP also differ during the injection molding process. For this reason, a mold filling simulation is performed in each iteration of the topology optimization to account for the resulting locally varying anisotropic material properties and residual stresses of the FRP in the simulation model on which the topology optimization is based. For a metal insert made of S700 and A3WG6 as FRP consisting of polyamide 6.6 with 30% glass fiber reinforcement, different designs result from the topology optimization in Tosca with and without application of the described method. By using the method, designs can be created that avoid premature failure of the cohesive zone. Compared to standard topology optimization in Tosca, higher reaction forces can be achieved without cohesive zone failure.