Electrification of the power train in vehicles will obviously have a big impact on the future of automotive industry. One key component of an electric vehicle is the inverter which dissipates energy by heat. Therefore, high temperature resistant printed circuit boards (HT-PCBs) are required instead of conventional ones based on FR4 for the control board and DCB substrates for the power board. As polymer based substrate materials for HT-PCBs, high temperature epoxy resins are employed at present. Within the BMBF funded project “HELP” it could be shown that halogen-free high temperature epoxy matrix systems feature good properties like a high glass transition temperature and low thermal expansion in thickness direction. Benzoxazines, a rather new class of high temperature resins, exhibit a low coefficient of thermal expansion, low water absorption, a high glass transition temperature and inherent flammability as described in literature [1]. The aim of this study was to investigate the potential of a Bisphenol-F-benzoxazine system blended with different ratios of a multifunctional epoxy resin for high temperature PCB application. Thermomechnical properties in dependence of the blend ratios were measured using Thermal Mechanical Analysis and Thermo Gravimetric Analysis as well as Differential Scanning Calorimetry. A high glass transition temperature of more than 190 °C and a CTE in thickness direction of less than 60 ppm/K could be achieved without adding any fillers which shows the high potential of the benzoxazine-epoxy blend systems as base materials for HT-PCBs. To transfer the properties of the neat materials to an applied system, laminates in laboratory scale were prepared and characterized, too. [1] Ishida H., Agag T., Handbook of Benzoxazine Resins, Amsterdam, Oxford: Elsevier B. V., 2011