Abstract: Astaxanthin was a fat-soluble lutein carotenoid with good antioxidant, anti-inflammatory and immunomodulatory activities. However, its poor oral bioavailability led to limited clinical application. Recently, in order to improve the bioavailability of astaxanthin, various types of nano-formulations had been widely studied. Nano-emulsion, liposome, solid lipid nanoparticles, chitosan and PLGA nanoparticles had been shown to effectively improve the oral bioavailability of astaxanthin. In this review, based on in vitro and in vivo studies, the research progress of nano-formulations for improving the oral bioavailability of astaxanthin were summarized, providing reference for the development of oral delivery of astaxanthin, and achieving its clinical application value in the future.