Echinacea purpurea (L.) Moench is a medicinal plant from North America, Europe, and Australia that has been traditionally used to treat the common cold, bronchitis, coughs, and inflammation of the pharynx and mouth. Furthermore, extracts of Echinacea purpurea (EP) exert various biological effects, such as antioxidant, antibacterial, and anti-inflammatory activities. However, the possible mechanisms of action of the immune-enhancing effects are yet to be elucidated. Therefore, this study investigated the role of EP extracts in the immune-enhancing effects of RAW264.7 cells and the underlying mechanisms of action. It was found that EP extracts considerably increased the protein expression of iNOS, COX-2, and mPGES-1 in RAW264.7 cells. Also, EP extracts increased NO production, phagocytic activity, and the expression of cytokines. Consistent with these results, phosphorylation of MAPKs (ERK, JNK, and p38) and NF-κB (IKKα/β, IκBα, and NF-κB p65) were induced after treatment with EP extracts. Finally, EP extracts caused a marked increase in activation of the TLR4-TRAF6-TAK1 pathway. These results suggest that the immune-enhancing effects of EP extracts are mediated through the TLR4-associated activation of the NF-κB and MAPK pathways in RAW264.7 cells. Thus, it is suggested that EP extracts could be considered as a potential immunostimulatory agent or functional food.