Growing concern about the environmental and health impacts of the use of plastic, a group of materials made of polymers and obtained from non-renewable sources such as oil, has encouraged scientists to investigate sustainable and environmentally acceptable alternatives to these materials. Among the wide selection of biomaterials, which require less energy during production, and are biodegradable, myceliumbased composites or MBCs stand out. MBCs are obtained by combining different types of mushrooms with agricultural residues, for example with wheat or hemp, which form the substrate for the growth of mushroom mycelium. The selected species mostly belong to white rot fungi, and the genus Pleurotus and Ganoderma are most often used for cultivation. The selection of the substrate, the type of mushroom, as well as the control of growth conditions during the production process of MBCs allows for the creation of diverse biodegradable materials that can compete with plastic products in terms of mechanical properties. Mycelial materials have been showing their potential for the past few years in various studies and applications, for example in the packaging and construction industry, while companies like Ecovative are paving the way on the market with their unique products. Ultimately, research suggests that composites made of mycelium have extraordinary potential to become an alternative to plastics, but further research is needed to realize the full potential of these materials.