In order to reduce the test time of MMP, according to the principle of interfracial tension disappearing, a new experimental method which is able to quickly determine the MMP is developed. In the experimental method, the main equipment is a rotatable high pressure piston-typed sample preparation container. In order to determine the MMP, the pressure when the oil is mixed with CO₂ is measured. Using the test method of two-phase contact process, the CO₂ MMP of reservoir oil in Chang six of Huaqing has been measured. Comparing with the test result of slim tube test, the MMP result based on two-phase contact process is very closed to the result based on slim tube test. The test method of two-phase contact process possesses features of both simple operation and short test time period.