Abstract: As a new resource of food, natural astaxanthin is by far the most powerful antioxidants found in nature.However, insolubility and instability of astaxanthin limited its diverse applications in the fields of food and medicine.Using micro / nano- encapsulation technology by encapsulating astaxanthin in a polymer- based wall material can improve the solubility and stability of astaxanthin. On the other hand, new materials and preparation technologies have to be developed to satisfy the strict requirements of food security and industrial production. The preparation methods and characteristics of the astaxanthin- encapsulated micro / nano- particles were introduced in this paper, and the new research progresses of micro / nano- encapsulation technology applied in functional food in recent years were reviewed.