Various factors, such as the adsorption pH, adjuvant dose, and adjuvant age, which affect the adsorption degree and immunogenicity of an antigen, were investigated.In addition, the effect of pH, antigen content, and adjuvant content on immunogenicity was also studied through animal experimentsWithin the ranges studied, a low pH for adsorption, freshly preformed gel, and low pH formulation for the combined DTwP-HepB vaccine were preferable for the adsorption of the antigens.In addition, a higher DT content was found to have a pos. effect on the HBsAg immunogenicity in the combined vaccine.Accordingly, considering the factors affecting the adsorption rate and immunogenicity of the antigens, a novel DTwP-HepB vaccine (40 Lf/mL of diphtheria toxoid, 15 Lf/mL of tetanus toxoid, 20 OU/mL of detoxified whole cell pertussis, 24 μg/mL of HBsAg, 24 μg Al/mL of Al(OH)3, gel, 776 μg Al/mL of AlPO4 gel, and pH 7.1) was developed, whose immunogenicity was comparable to the case of administrating, sep. and simultaneously, a combined DTwP vaccine (40 Lf/mL of diphtheria toxoid, 15 Lf/mL of tetanus toxoid, 20 OU/mL of detoxified whole cell pertussis, 300 μg Al/mL of ALPO4 gel, and pH 7.1) and mono HepB vaccine [HepavaX , 24 μg/mL of HBsAg and 500 μg Al/mL of Al(OH)3 gel], which satisfies the potency criteria of the K-FDA for a combined DTwP vaccine and mono HepB vaccine.