In current research design and optimisation of cargo truck cabin seat plate has been executed. In particular study a traditional steel sheet material has been replaced by thermoplastic glass/polypropylene composite. Such a design should enable a possibility of quick one shot manufacturing of composite structure and in addition it provides a significant weight savings. As a basis for redesign serves topological optimisation based on existing metallic part geometry which has been imported in finite elements code ANSYS. The load case corresponding to the car crash seat pull test according to ECE-R14 standard has been applied for selection of material savings and for additional reinforcement. Preliminary optimisation results indicated areas where volume of material should be increased or in contrary decreased. It was confirmed that the special treatment should be given to areas under front and rear load bearing points in order to prevent them from the local stress concentration.