The objective of this study is to investigate the pharamacokinetic parameters of decursinol following oral administration in Sprague-Dawley rats. The plasma concentration of decursinol was determined by LC/MS with APCI positive mode. The m/z value of decursinol was observed at 247. Following oral administration of decursinol extract, the apparent clearance was , the absorption half life was , the elimination half life was , and the apparent volume of distribution was . The LC/MS method was successfully applied to the pharmacokinetic study of decursinol.