Mycelium composites represent an attractive alternative to turn to more sustainable construction materials. Mycelium, the vegetative growth of fungi, is formed by a network of hyphae (elongated fungal cells). This mycelium network has the capacity to partly degrade carbon-rich fibres while binding them together. In this way, a biological process can serve to create biobased composite materials, in which the fungal biomass functions as inherent adhesive while the fibres provide the structural support. As this is an efficient biological process, creating completely natural materials, mycelium composites have the potential to be a low-impact and healthy alternative or addition to conventional building materials. Finished mycelium composites can be heat-pressed into sheet materials. In this research, mycelium composites are heat-pressed to explore their potential as board material. Through systematic study of the parameters pressure, time and temperature, the most promising combinations were determined by bending strength performance. The used mycelium composites consisted of straw fibres, or a combination of straw fibres and cellulose, bound together with the fungus Ganoderma resinaceum. As opposed to literature this project found bending strengths within the range of glue-bound board materials such as particleboard and MDF. In conclusion, the present research investigated the relation between the heat press process mechanical properties of the material. In particular the influence of the combination of pressure, time and temperature on the bending strength of the material was studied. Considering these aspects, the research revealed that mycelium composites have the potential to become a completely natural, low-impact building material.