The preservatives in 32 commercial liquid preparations of crude drugs have been analyzed by using high performance liquid chromatography. Benzoic acid (BA) and p-hydroxybenzoates were separated with mobile phase of $MeOH-H_2O$ (70:30) (pH 7.0) at a flow rate of 0.9ml/min. BA, sorbic acid and dehydroacetic acid were separated with mobile phase of $MeOH-H_2O$ (40:60) (pH 4.5) at a same flow rate. In addition, the pH values of the preparations were investigated. It was found that BA was used in most of the preparations.