In order to further explore the migration rule of alkali/surfactant/polymer（A/S/P） system in the reservoir

guided by the reservoir engineering

surfactant chemistry and oilfield chemistry

and aimed at the fluid properties and geological characteristics

we conducted the research on change rule of viscosity

IFT tension and displacement effect of A/S/P system

and discussed the relative mechanism based on the dynamic testing result of single component concentration of compound system. The results showed that during the displacement process of A/S/P system

the polymer

surfactant and alkali presented different along-range retention characteristics

the chromatographic separation phenomenon occurred

the decrease rate of surfactant concentration was much higher than that of polymer and alkali

and both the ultra-low interfacial tension and high viscosity could only keep the length of 1/3 well distance. The contribution rate of ultra low tension was limited in the A/S/P flooding; about 60 % oil was not recovered by compound system under the condition of ultra low tension. If the A/S/P system can keep lower IFT and give consideration to proper viscosity

we can acquire the better displacement effect.