The function of emulsion adjuvants in vaccine antigen delivery remains unclear. To investigate the roles of emulsion adjuvants in cross presentation of exogenous antigens, a series of emulsions were prepared for both in vitro and in vivo studies. Bone marrow-derived dendritic cells (BMDCs) were treated with the adjuvants and analyzed by flow cytometry for the expression of costimulatory molecules. The activation of antigen-specific T cells in vitro was determined with B3Z cells. Antibody secretion in the draining lymph nodes of emulsion adjuvant-treated animals was measured by enzyme-linked immuno-spot (ELISPOT) assays, and antigen-specific proliferation of cells was conducted to examine the roles of emulsion adjuvants in antigen delivery.