Provided is an acidic oil-in-water type emulsified composition, containing an oil or fat having a diglyceride content of 30 wt. % or greater an egg yolk, and a water soluble soybean polysaccharide.The acidic oil-in-water type emulsified composition of the present invention is excellent in taste and appearance stability, has resistance against pressure-induced shear stress which occurs upon preparation or use, shows less changes in physical properties, for example, viscosity reduction can be suppressed, and is free from appearance change such as oil/water separation. Thus, it has a stable quality.