Abstract: Amid global efforts toward sustainable development and plastic pollution reduction, polylactic acid (PLA) fiber, as a high-performance bio-based and biodegradable fiber material, has demonstrated significant application potential in the textile, medical, and other fields due to its excellent biocompatibility, processability, and environmental friendliness. This paper analyzes the entire technological chain from raw material preparation, chip synthesis, to fiber formation and end-use applications. It compares the technical characteristics and industrialization progress of direct polymerization of lactic acid and ring-opening polymerization of lactide, discusses research pathways for achieving fiber functionalization and high-value application through physical blending, chemical modification, and process innovation, and summarizes the product development and performance advantages of PLA fibers in fields such as home textiles and medical hygiene. Finally, the paper outlines key directions in non-food feedstock development, high-performance enhancement, and low-cost large-scale production, aiming to provide theoretical references and practical insights to support the continuous innovation and green development of the bio-based fiber industry.

Key words: polylactic acid fiber; bio-based fiber; biodegradable fiber; biodegradability; development trends