Lignocellulosic biomass has received much attention as a renewable and abundant feedstock for eco-friendly production of valuable fuels and chemicals. The transformation, typically, involves two steps: depolymerization of biomass into a liquid intermediary product called bio-oil through biochemical or thermochemical processes followed by its upgrading or chemical conversion. Compared to crude oil, bio-oil contains large amount of oxygenate compounds such as alcohols, phenols and carboxylic acids. For fuel application, the oxygenates should be reduced or removed by catalytic processes such as hydrodeoxygenation or zeolite cracking. In the production of chemicals such as resins and polymers, the functional groups of oxygenate compounds are involved in the desired reactions. However, high oxygen content of bio-oil leads to challenges in the development and commercialization of such processes. This chapter reviews the value chain from biomass to green fuels and useful materials. The respective processes and catalysts are reviewed and the challenges are discussed. The latest developments in each field are also introduced.