<p>Polyhydroxyalkanoates (PHA) have gained significant attention as biodegradable and biocompatible polymers with promising applications in various industries, including packaging, biomedical, and agriculture. The growing demand for sustainable alternatives to petrochemical-based plastics has fueled the expansion of the PHA market, with increasing research efforts focused on cost-effective production and improved material properties. This review provides a comprehensive analysis of the global market trends and potential applications of PHA, highlighting the challenges associated with large-scale commercialization. The paper further explores the different types of PHA, detailing their physicochemical and mechanical properties. These properties, such as mechanical strength, biodegradability, and thermal stability, influence their suitability for various applications. To improve the functional properties of PHA, researchers have explored various modification strategies, including biological, chemical, and physical approaches. Biological modifications involve metabolic engineering and microbial strain development to optimize monomer composition and improve polymer yield. Chemical modifications, such as grafting, blending, and copolymerization, enhance mechanical flexibility, hydrophilicity, and processability. Physical changes, including the addition of other polymers and fillers, further tailor the material’s performance for specific applications. By addressing the advancements and limitations in PHA modifications, this review aims to provide insights into the future directions of PHA research and development, supporting the transition toward sustainable biopolymer-based industries.</p> Graphical abstract <p></p>