The work aims to introduce the chemical composition and structure of lignocellulosic materials and review the research progress of the common pretreatment methods of lignocellulosic materials and their application in the synthesis of polyhydroxyalkanoates (PHA). Based on the analysis and summary of the research status and achievements at home and abroad, the influence of common pretreatment methods of lignocellulosic materials, such as steam explosion pretreatment, hot water pretreatment, acid pretreatment, alkali pretreatment, ammonia fiber explosion pretreatment, ionic liquid pretreatment, organic solvent pretreatment, etc., on the saccharification rate of lignocellulosic materials and their application in synthetic packaging materials polyhydroxyalkanoates were emphatically discussed. Different lignocellulosic materials and different pretreatment methods had a great influence on the content of total sugar and the type of monosaccharide in total sugar and the mass fraction of monosaccharide in total sugar. Meanwhile, different total sugars (including different monosaccharide types and the mass fraction of monosaccharide in total sugar) were used as carbon source for microbial fermentation to produce PHA, which would form monomer of PHA and different mass fractions of monomer in PHA, thus forming PHA with different properties and widely used in the field of packaging. There are many studies on optimizing pretreatment and enzymolysis technology used to improve the yield of fermentable sugar at home and abroad. Compared with other pretreatment technologies, hot water pretreatment technology is featured by low production cost and environmental protection. Therefore, the development of economic hot water pretreatment technology suitable for large-scale industrial production is the focus of attention in the future.