In this research, a lab study was conducted on the process of injection Of Surfactant Dodecyl benzene Sodium Sulfonate [Wetconat-P1220EH (DDBSCa)] into a lab prepared matrix model consists of Marble that physically simulates the reservoir properties of Jaribee producing formation in Dero oil field. An injecting operation of the said surfactant was applied on the rock model using The Following Volumetric ratios          (15, 30 and 50% PV), then the injection was continued at each ratio using the displacement liquid until the Volumetric ratio 250%PV  in order to guarantee an efficient displacement . Through the results of the displacement processes, the change of the following factors in relation with the ratio of the injected liquid to the volume of the pores of the model was studied O.F.D: oil displacement factor, W: water percentage in the produced  liquid, and Ra: recoverability. represents the ratio of the produced oil volume at every injecting process to the accumulating volume of the injected liquid in the same stage. Ra=V_O/V_T . To compare the efficiency of displacement using the said surfactant with the efficiency of water injection (currently applied in Dero field), the model was prepared for water injection (Water flooding) by cleansing by kerosene and water, then dried and               re-saturated with oil. A comparison between the change of the aforementioned factors of water injection and surfactant injection was graphically performed . The results of the graphical comparison of both injecting methods implied an obvious increase of (O.F.D) and (Ra) factors when injecting the surfactant at all studied injection ratios than that of the water injection