A stable complex oil-in-water emulsion which is useful in the cosmetic, pharmaceutical or food fields. The stable complex oil-in-water emulsion is formed by the mixing of individual oil-in-water emulsions, each individual emulsion being obtained from an air/water pre-emulsion of a preferably-nonionic surfactant; a cosurfactant selected from hydrophilic compounds, preferably with at least one hydroxyl group selected from polyols; and an aqueous phase. A method of preparing a stable complex oil-in-water emulsion whereby individual oil-in-water emulsions, chosen for properties desired in the stable complex oil-in-water emulsion, are optionally diluted and mixed without exerting a shear force.