E EOR process consist of fluid injection or several types of fluid into a reservoir to displace oil . In some countries, chemical injection has been able to increase oil recovery until 28% (Hestueni et al, 2010). The purpose of this research is to see the effect of formation water salinity and the concentration of surfactant to oil recovery. This research was conducted at the Laboratory of EOR Trisakti university Jakarta, by analyzing the results of measurement of density, viscosity of the solution, as well as compatibility testing and IFT test. From the compatibility test and IFT impairment test, optimum surfactant solution is surfactant solution with a concentration of 0.1%, 1% and 1,25%. Based on the core flooding on three sandstone core samples were used, shows the largest oil recovery factor (RF) contained in the injection solution of surfactant salinity 1000 ppm with surfactant concentration 1.25% in which a total oil recovery achieve 99.01 % while the lowest RF there on the a solution of surfactant 0.1% and salinity 0 ppm with total oil recovery factor achieve 62.34 %. Analysis results of oil recovery on the core flooding is known there are several factors affecting the decrease in interfacial tension of the surfactant solution is the salinity of formation water, the concentration of surfactant solution and the influence of temperature.