Abstract: In order to eliminate the interference from carbonate on the determination of chlorine, a new IonPac AS23 column was selected in determination of chlorine in marine sediments through the comparative trial between commonly used IonPac 14 column and IonPac AS 23 column. The causes led to lower concentration results of chlorine in marine sediments were discussed when kraft bag was used for sample storage. Under the optimized determination condition, the method has been applied to the determination of chlorine in national standard marine sediments. The results are in agreement with the certified values with precision of less than 2.66%RSD.