ABSTRACTBiomass is the term given to naturally‐produced organic matter resulting from photosynthesis, and represents the most abundant organic polymers on Earth. Consequently, there has been great interest in the potential exploitation of lignocellulosic biomass as a renewable feedstock for energy, materials and chemicals production. The energy sector has largely focused on the direct thermochemical processing of lignocellulose via pyrolysis/gasification for heat generation, and the co‐production of bio‐oils and bio‐gas which may be upgraded to produce drop‐in transportation fuels. This mini‐review describes recent advances in the design and application of solid acid catalysts for the energy efficient upgrading of pyrolysis biofuels. © 2015 Society of Chemical Industry