The work aims to realize the low-cost, large-scale production of PHAs and the high-value utilization of lignin through the study of lignin biosynthesis of polyhydroxyalkanoates (PHAs). The main strains and existing problems of lignin-degrading bacteria and biosynthetic PHAs at home and abroad were summarized and analyzed, and the types of lignin substrates for biosynthetic PHAs and the related research progress of process optimization strategies in the synthesis process were introduced. At the same time, the relevant applications of PHAs in the field of packaging were summarized. In the process of lignin biosynthesis of PHAs, the conversion rate of lignin substrates and the yield of PHAs could be effectively improved by screening lignin-degrading bacteria, cultivating PHAs synthesis bacteria, and optimizing the synthesis process and influencing factors of PHAs, thereby reducing the production cost. Although the process of converting lignin into PHAs faces some challenges, with the continuous innovation of technology and the optimization of production process, green bioplastic PHAs synthesized with lignin as substrate will have broad application prospects and development space in the field of packaging, which will inevitably promote the development of packaging materials in the direction of greening and safety.