With the continuous depletion of fossil resources and the deterioration of the global climate, it is particularly urgent to find green and sustainable renewable resources to replace non-renewable resources. Renewable biomass, which converts and stores light energy into chemical energy through photosynthesis by green plants, has received widespread attention due to its simultaneous resource and energy properties. Therefore, this article focuses on lignocellulose, an important component of biomass, in the fields of chemical conversion and high-value-added chemical preparation. A detailed review was conducted on the application of catalysts in biomass bio-char, bio-oil, bio-gas, and high-value added chemicals and their derivatives, represented by 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA). At the same time, the difficulties and challenges encountered by catalysts in biomass conversion were analyzed, and new ideas were proposed for future development directions, so as to provide new development pathways for efficient and green conversion of biomass into biomass energy and high-value-added chemicals.