A water-in-oil type oil adjuvant vaccine comprises 20 to 90% by weight of an oil phase A) which is in a liquid state at ordinary temperature; 0.5 to 30% by weight of an emulsifying agent comprising a non-ionic surfactant B) which is a partial ester derived from a polyhydric alcohol carrying at least three hydroxyl groups and a fatty acid and which is in a liquid state at 40°C and a polyoxyethylene (20 to 60 moles) hydroxy fatty acid triglyceride C); and 5 to 75% by weight of an aqueous phase D) containing a biologically acceptable and effective amount of antigens, and optionally E) 0.01 to 10% by weight of an amino acid or a salt thereof and 0.01 to 10% by weight of a nonreducing sugar or a sugar alcohol having at least 5 hydroxyl groups in the molecule. In addition, a water-in-oil-in-water type oil adjuvant vaccine comprises the foregoing water-in-oil type oil adjuvant vaccine as an internal phase and an outer aqueous phase F) comprising 0.2 to 20% by weight of an emulsifying agent which comprises a non-ionic surfactant and which has an overall HLB value of not less than 10. The oil adjuvant vaccines show a high ability to induce an antibody-production over a long period of time and are excellent in requirements for medicines such as stability and safety.