The complexity of fluid flow during reservoir development often renders conventional water injection or stimulation measures ineffective. Traditional water-soluble tracers used for monitoring water injection fronts have significant limitations in revealing the remaining oil distribution and oil phase flow behavior. To address these limitations，this study aimed to establish a rapid method for the separation and detection of oil-soluble tracers in crude oil based on gas chromatography （GC） technology. Through solvent screening experiments，methanol was selected as the optimal extractant due to its minimal extraction of crude oil components and low signal interference. To tackle the issues of water interfering with extraction efficiency and residual heavy components prolonging the analysis cycle，an optimized sample pretreatment process was proposed. This involved in adding isooctane （20 % mass fraction） and excess K₂CO₃ to the tracer-containing crude oil. After dehydration via stirring，ultrasonic treatment，and centrifugation，the methanol extract was frozen at - 32 ℃ to remove impurities before analysis by the gas chromatograph. Experimental results demonstrated that the pretreatment method effectively removed water and significantly reduced interference from heavy oil components. The precise separation and identification of signal peaks for 38 oil-soluble tracers could be achieved within 10 hours using a single injection. The method is rapid and efficient，meeting the requirements for field monitoring of oil phase flow and reservoir characterization.