The cleaner and technologically feasible alternative to fossil fuels is biocrude oil, a liquid fuel derived from renewable biomass. Its production accounts for the sustainable solution against the increasing energy demand and greenhouse gas emission. Technologies developed to produce renewable energy from biomass include: physical, namely drying, pressing, crushing, and palletization; biochemical, including fermentation and anaerobic digestion; and thermochemical, which include pyrolysis, gasification, liquefaction, and combustion pathways. Of these, the thermochemical pathways have gained much attention since they allow for high-energy output and efficiency. Thermochemical processes, especially pyrolysis and hydrothermal liquefaction, show significant potential in the conversion of biomass into biocrude. Pyrolysis is the thermal decomposition of organic material in the absence of oxygen that produces bio-oil, biochar, and syngas. In contrast, the hydrothermal liquefaction transforms the biomass into a liquid product in an aqueous environment under high temperature and pressure. Furthermore, pyrolysis produces a higher yield of bio-oil, exhibiting lower heating value and stability due to its high oxygen content, whereas hydrothermal liquefaction produces biocrude with lesser oxygen content and heating value, thus more similar to conventional liquid fuels. The process, however is highly energy-intensive and, also requires downstream upgradation to meet fuel quality standards. This chapter reflects the current state of research and development with emphasis on important issues, opportunities, recent technological developments, and techno-economic feasibility of biomass pyrolysis and hydrothermal liquefaction to produce biocrude oil.