Abstract: Contrast to regular mud acid, foamed acid is superior in many aspects, such as slow reaction rate, tiny corrosion rate, easy to flowback, slight damage, etc., acid diversion in the heterogeneous reservoir can be realized by the use of foamed acid. It is also an ideal acid system for the stimulation of low pressure, low permeability and high water cut inhomogeneous reservoir. In this paper, taking the half-life period of the foam and the foaming volume as the main evaluation indicator, we evaluate the behavior of the addictives used in foamed acid system by stirring, and optimize the effective foamed acid system through the use of orthogonal array test method. Results show that the foamed acid has better retarded and anti-corrosive effect. The higher the foam mass is, the better the retarded and anti-corrosive effect are. Foamed acid has satisfactory diversion effect. After the simulation, permeability of the dual core increases, and the permeability differential is small.