A novel, low-cost, and fully recyclable thermoplastic material is produced from liquefied lignocellulosic biomass and natural fibers. The matrix, which is the heavy fraction of the liquefaction product, is characterized in terms of molecular weight distribution, density, viscosity, softening point and tensile strength. It is possible to increase the mechanical strength of the matrix by a factor of up to 100 by reinforcing it with flax fibers. Specifically, the tensile strength increased from 0.4 MPa for the non-reinforced matrix, to 55 MPa for the matrix/flax composite with a fiber content of 20 wt %. These values are comparable to conventional thermoplastics, such as poly(methyl methacrylate), polyvinyl chloride, or polystyrene.