Abstract: Biomass is the sole renewable carbon resource that can be transferred into gas, liquid and solid fuels as well as other chemicals. As the fossil energy will be exhaustive, humans pay more attention to the problems of global environment. Many scholars and researchers in the world have been focusing on the research and development of biomass energy to substitute for fossil energy. The clean and high quality gas, liquid or solid fuels converted from renewable biomass resource by different ways were described in the course series. Preparation of bio-oil made by high-pressure liquefaction and fast pyrolysis was introduced in this paper, including research status, technics and equipments. Based on the summarization of characteristics of bio-oil derived from pyrolysis of biomass, research status on up-grading process of the bio-oil was reviewed, too, including physical up-grading technologies (dehydration, adding solvent, and emulsification) and chemical up-grading technologies (hydrogenation, catalytic pyrolysis, catalytic esterification, steaming reforming). The mechanism, advantages and disadvantages of these up-grading methods were analyzed. It was pointed out that the bio-oil from pyrolysis of biomass will substitute gasoline and diesel oil with the development of preparation and up-grading technology, which will be taken more and more attention.