Abstract: Objective: to establish a capillary gas chromatography derivatization method for determination of 3-amino-1,2-propanediol of intermediate IOHEXOL as X-CT contrast medium of the non-ion type. Method: the sample was derived for 30 min with TFAA under 50℃,then injected into SE-54(30 m×0.25 mm×0.25 μm)capillary column by GC with FID detector. Result: optimization of experiment was chosen and the relative standard deviation was 0.921% and the additive recovery was 99.2%.The repeatability of the experiment is good and the method is simple and accurate.