Abstract: A method to determine (R)-(-)-3-Chloro-1, 2-propanediol in compounds by gas chromatography(GC) is set up. With the FID detector temperature:290℃, inlet temperature:280℃, split ratio 1:1, carrier gas:N₂, flow rate:5 mL/min. The column temperature program:initial temperature 75℃ hold for 3 min, heat up to 150℃ at a rate of 20℃/min, and then heat up to 180℃ at a rate of 8℃/min, at last heat up to 240℃ at a rate of 30℃/min and hold for 12.5 min. The blank solution had no interference on the solvents to be tested, (R)-(-)-3-Chloro-1, 2-propanediol peak was well separated from other residual solvent peaks, so the specificity was good. The LOQ was 2.06 ng, the LOD was 6.58 ng, and the linearity was acceptable. The linear relationship between (R)-(-)-3-Chloro-1, 2-propanediol concentration and peak area, in the range of 80~200 μg/mL was good, linear equation:y=2.558 8x-62.469, correlation coefficient r was 0.999 4. The same solution has been injected continuously for 6 times, and the RSD among the results was less than 1.0%.The RSD of the same homogenous sample was less than 1.5%, so the method reproducible. All the results of spiked recovery were in the range of 98%~102%, so the method is accurate. The method is suitable for testing (R)-(-)-3-Chloro-1, 2-propanediol in choline.