C ompletion fluid is a fluid used in an advanced stage after drilling(production and maintenance of wells) that contain very little solid or non solidfluid. Besides being used to withstand the pressure of the formation, completionfluids are expected to clean the dirt or remnants of the drilling mud. Completionfluid 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 influencedby several factors such as the quality of the completion fluid used, pressure, andconcentration of completion fluid. If the completion fluid to be pumped into thereservoir has good quality, then it will be obtained an optimum permeabilityenhancement.This research was conducted in the Laboratory Analysis of Reservoir rocksTrisakti University. Core samples used are sandstone rocks of 5 pieces which willbe injected with a phosphate-based completion fluid additive EDTA was done byvarying the concentration of phosphate (5%, 10%, 15%, 20% and 25%).Parameters tested include the physical properties of rocks sandstone, completionfluid composition, fluid volume, density, the specific gravity, viscosity, porosityand permeability of rocks.The size of the success factors for the use of completion fluid is influencedby several factors such as the quality of the completion fluid used, pressure, andconcentration of completion fluid. If the completion fluid to be pumped into thereservoir has good quality, then it will be obtained an optimum permeabilityenhancement. This research was conducted in the Laboratory Analysis of Reservoir rocksTrisakti University. Core samples is sandstone rock as much as 2 pieces that willbe injected with a phosphate-based completion fluid additive EDTA was done byvarying concentrations of phosphate (5%, 10% and 15%). Parameters testedinclude the physical properties of rocks sandstone, completion fluid composition,fluid volume, density, the specific gravity, viscosity, porosity and permeability ofrocks. After calculation and analysis of the survey conducted in the laboratory, itis known that An increase in porosity value NOT ANY injected rock phosphateWITH completion fluid additive EDTA . It indicates that the injection of fluidsinger completion phosphate additive EDTA WITH NOT have any influenceAgainst porosity value . Porosity value of the sample of S - 1 differences is equalto 19.50 and the value of the porosity of the sample of S - 1 differences is equal to19.25 % which is very good category .Injection of fluid completion based phosphate also shown to increase thepermeability of rocks sandstone, the sample S-1 meniliki permeability initial oil9.503 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-2meniliki initial oil permeability values Md 12.861, after rising successivelyinjected into mD 17.709; MD 21.954; MD 24.865. Based on an analysis of theincrease in its permeability persetase, phosphate injection with the most effectiveadditive EDTA is obtained when the injection with a concentration of 5% in thesecond sample of the sample S-1 amounted to 42.11% and the sample S-2amounted to 37.69%