Organocatalysis using small-molecule organic compounds as catalysts has risen to prominence in organic synthesis and polymer synthesis. However, its application in biorefining for catalytic biomass conversion and upgrading into sustainable chemicals, materials, and biofuels has come to light only recently. This emergence of applying organocatalysis for biorefining has not only broadened the scope of organocatalysis and offered metal-free “greener” alternatives for biomass conversion and upgrading, it has also showed some unique activity and selectivity in such transformations as compared to metal-mediated processes. This review captures highlights of this emerging area by focusing on utilization of organocatalytic means for catalytic conversions of cellulose, glucose and fructose, upgrading of furaldehydes, and organocatalytic polymerization of biomass feedstocks.