OBJECTIVE： To determine the contents of citric acid in fentanyl citrate raw materials and its injection by ion chromatography. METHODS： The determination was performed on Thermo Dionex IonPacTM AS11-HC column with mobile phase consisted of potassium hydroxide （gradient elution） at the flow rate of 1.0 mL/min. The column temperature was 35 ℃， and sample size was 20 μL. The detector was suppressed conductivity detector. RESULTS： The linear range of citric acid were 0.115 7-74.05 μg/mL（r＝0.999 5）. The limit of quantitation was 0.115 0 μg/mL， and the limit of detection was 0.040 0 μg/mL； RSDs of precision， stability and reproducibility tests were all lower than 2.0％； the average recoveries were 99.6％-101.5％ （RSD＝0.68％，n＝9）.  CONCLUSIONS： The method is environmentally-friendly and simple with good accuracy and precision， and suitable for the contents determination of citric acid in fentanyl citrate raw materials and injection.