The global energy and chemical vectors are undergoing rapid alteration to meet the incremental competition, social challenges, and the growing efforts for a safe, green, and sustainable future. The transition to new technologies, based on sustainable and renewable energy and chemical resources, represents a viable backbone of the future economic cycle. Thus, the future scenario of refineries will be established by the ongoing substitution of fossil fuel-derived products with renewable alternatives. Compared to fossil-based resources, biomass has been a significant resource of energy, fuel and chemicals due to possessing a much shorter forming duration and reducing greenhouse gas emissions. A wide variety of products can be obtained from biomass such as gas fuels (H2 and CH4), liquid fuels (biodiesel, methanol, ethanol, and vegetable oil), solid fuels (hydrocarbons and biochar), and valuable chemicals from various applications. Therefore, this Special Issue plans to give an overview of and provide selected contributions on advances in the sustainable approaches for biomass valorization and obtained product applications. Articles should cover, but are not limited to, the following topics related to biomass transformation: Biomass pretreatments Thermochemical conversion of biomass Biochemical conversion of biomass Chemical conversion of biomass Bio-based model components transformations Biochar and hydrochar modifications and applications Biomass derived carbon dots