Jellyfish has recently attracted much attention for various applications, including functional foods due to its abundance of collagen. Jellyfish collagen, extracted from Nemopilema nomurai, was found to stimulate murine macrophage-like J774.1 cells. However, few reports have determined the immunostimulatory effects of jellyfish collagen on the innate immune response. We herein demonstrate the effect of jellyfish collagen on mouse bone marrow-derived dendritic cells (BMDCs). Jellyfish collagen stimulated TNF-α, IL-6, IL-1β and IL-12 production by BMDCs as the result of the elevation of gene expression level of these cytokines. In addition, jellyfish collagen-treated BMDCs have more wrinkles and longer pseudopodia on the cell surface compared with the control cells. Jellyfish collagen also stimulated cell-surface MHC-II expression level. Furthermore, jellyfish collagen downregulated phagocytosis capacity of BMDCs. Thus, our findings suggest that JC has the potential to activate DCs and thereby contribute to health promotion.