C Completion fluid is a fluid used in an advanced stage after drilling (production and maintenance of wells) that contain very little solid or non solid fluid. Besides being used to withstand the pressure of the formation, completion fluids are expected to clean the dirt or remnants of the drilling mud. Completion fluid pumping method is also one way to increase the permeability of rocks. The size of the success factors for the use of completion fluid is influenced by several factors such as the quality of the completion fluid used, pressure, and concentration of completion fluid. If the completion fluid to be pumped into the reservoir has good quality, then it will be obtained an optimum permeability enhancement. This research was conducted in the Laboratory Analysis of Reservoir rocks Trisakti University. Core samples used are sandstone rocks of 5 pieces which will be injected with a phosphate-based completion fluid additive EDTA was done by varying the concentration of phosphate (5%, 10%, 15%, 20% and 25%). Parameters tested include the physical properties of rocks sandstone, completion fluid composition, fluid volume, density, the specific gravity, viscosity, porosity and permeability of rocks. The size of the success factors for the use of completion fluid is influenced by several factors such as the quality of the completion fluid used, pressure, and concentration of completion fluid. If the completion fluid to be pumped into the reservoir has good quality, then it will be obtained an optimum permeability enhancement. iv This research was conducted in the Laboratory Analysis of Reservoir rocks Trisakti University. Core samples is sandstone rock as much as 2 pieces that will be injected with a phosphate-based completion fluid additive EDTA was done by varying concentrations of phosphate (5%, 10% and 15%). Parameters tested include the physical properties of rocks sandstone, completion fluid composition, fluid volume, density, the specific gravity, viscosity, porosity and permeability of rocks. After calculation and analysis of the survey conducted in the laboratory, it is known that An increase in porosity value NOT ANY injected rock phosphate WITH completion fluid additive EDTA . It indicates that the injection of fluid singer completion phosphate additive EDTA WITH NOT have any influence Against porosity value . Porosity value of the sample of S - 1 differences is equal to 19.50 and the value of the porosity of the sample of S - 1 differences is equal to 19.25 % which is very good category . Injection of fluid completion based phosphate also shown to increase the permeability of rocks sandstone, the sample S-1 meniliki permeability initial oil 9.503 mD, once injected phosphate with an additive EDTA 5%, 10% and 15%, against a row to be 13.506 mD ; MD 16.719; MD 18.560. And the sample S-2 meniliki initial oil permeability values Md 12.861, after rising successively injected into mD 17.709; MD 21.954; MD 24.865. Based on an analysis of the increase in its permeability persetase, phosphate injection with the most effective additive EDTA is obtained when the injection with a concentration of 5% in the second sample of the sample S-1 amounted to 42.11% and the sample S-2 amounted to 37.69%