In this study extraction, optimization and characterization of Ruta chalepensis oil which has beenrnrecognized as good sources of crude oils, essential oils and other important chemicals wasrninvestigated. The crude oil was extracted by soxhlet apparatus using hexane as a solvent. Thernprocess parameters such as extraction temperature, time, and solid mass to solvent ratio werernoptimized for maximum yield of crude oil using response surface method. The maximum crude oilrnyield (16.68 %) was obtained at extraction temperature of 85rnornC, extraction time of 6 hrs and solidrnmass to solvent ratio of 13. Physico - chemical properties of the crude oils studied for the optimumrnyield show that the oil is a solidifying oil at room temperature having dark green colour with arnpleasant smell having melting point of 50oC, boiling point of 160 oC, specific gravity of 0.725 andrnPH 4.49-5.24 and characterized by having acid value 6.73mg KOH/gram, peroxide value 5.023rnmilliequivalents of active O2/ kg, iodine value 0.50706 gram I2 /100g, saponification value 196mgrnKOH/g. Ruta chalepensis crude oils extracted in incubator shaker using solvents ethanol, methanol,rndistilled water, diethyl ether and hexane were compared with the Ruta chalepensis crude oil extractrnusing soxhlet extractor of the optimum yield and shows varied value of total phenolic compoundrnand antioxidant activity evaluated using both maximum inhibition effect and IC50. The totalrnphenolic compounds are arranged in decreasing order as follows: aqueous extract> methanolrnextract> ethanol extract> diethyl ether extract> optimized hexane extract of soxhlet extractor >rnhexane extract by incubator shaker. Methanolic crude extract has maximum antioxidant activityrnfollowed by ethanol crude extract in terms of both maximum inhibition effect and IC50. and Rutarnchalepensis crude extract oil extracted using soxhlet extractor has appreciable antioxidant activityrnthan that of aqueous extract, diethyl ether and hexane extract of incubator shaker in terms of IC50rn.The chemical composition of essential oils extracted from Ruta chalepensis using Clevengerrnhydro steam distillation and identified using GC-MS have 2-undecanone (methyl nonyl ketone)rn(31.74), 1-dodecene or Î±-Dodecene(13.591), Tridecene (13.189), 2-Nonanone (methyl heptylrnketone) ( 9.573) ,2-tetradecanol (4.856) as the major components and the chemical structure ofrnthese compounds possess the functional group of ketones, alkenes which is one type ofrnhydrocarbons and alcohols being dominated by ketones followed by alkenes and alcoholsrnrespectively.rnKey words: Response surface methodology, Total Phenolic compound, antioxidant, Rutarnchalepensis, essential oil and GC-MS.