The immunoregulation and immunopotentiation of Polysaccharides of Atractylodes macrocephala Koidz (PAMK) have been widely demonstrated. Nanostructured lipid carriers (NLC) have high drug loading capacity for lipophilic and hydrophilic drugs, and have good biocompatibility and high bioavailability. In this study, the effect of PAKM-NLC on the surface molecule expression of bone marrow-derived dendritic cells (BMDCs) in vitro was investigated by flow cytometry, and the cytokines secreted by dendritic cell supernatants were detected by ELISA. The results showed that compared with other control groups, PAMK-NLC could significantly increase the expression of CD80 and CD86 and promote the secretion of IL-1β, IL-12, TNF-α and IFN-γ, indicating that PAMK-NLC have a more pronounced effect on the maturation and differentiation of BMDCs. In addition, effects of PAMK-NLC nanoparticles on OVA-immunized mice were explored. Compared with other control groups, PAMK-NLC-OVA can significantly promote the production of OVA-specific antibodies in serum, stimulate the secretion of cytokines, increase the proliferation rate of spleen lymphocytes after OVA re-stimulation, and induce stronger activation of CD3(+)CD4(+) and CD3(+)CD8(+) lymphocytes. As an adjuvant of OVA, PAMK-NLC has a better immunological enhancement effect than PAMK or blank NLC, and has good adjuvant activity.