Abstract: A method for simultaneous quantitative determination of 20 synthetic cannabinoids (SCs) in electronic cigarette oil by gas chromatography (GC) has been established. The samples were extracted using methanol. The initial temperature of the column was 250 ℃ and stayed for 1 min, and then the temperature was rised to 310 ℃ by the rate of 10 ℃/min and stayed for 21 min. Combined with the external standard method, the 20 SCs in electronic cigarette oil were successfully identified. The 20 SCs had a good linear relationship between 1.0~100.0 μg/mL, and the correlation coefficients (r) were higher than 0.999. The limits of detection (LODs) were 0.01~0.11 μg/mL, and the limits of quantitation (LOQs) were 0.03~0.36 μg/mL. At the three spiked levels (2, 10, 50 μg/mL), the spiked recoveries ranged from 83.74% to 114.82%, the relative standard deviations (RSDs, n=6) were between 0.44% and 4.11%. The 10 suspicious samples seized by the public security authorities were analyzed, and 4F-ABUTINACA, MDMB-4en-PINACA, ADB-BUTINACA, 4F-MDMB-BUTICA, 5F-MDMB-PICA and MDMB-BUTINACA were detected, the content were between 0.0050% and 0.2009%. The method is accurate, simple and rapid, which could satisfy the requirements of relevant identification work.