Active components were extracted from Angelica gigas Nakai by subcritical-water extraction (SWE) with the purpose of determining how the extraction conditions affect the SWE of antioxidant properties and active components (nodakenin and decursin), and to compare pilot-scale SWE (8 L) and conventional extraction methods. The extraction yields of nodakenin and decursin in the pilot-scale system were highest at 150 degrees C for 10 min and 190 degrees C for 15 min, respectively. The extraction yield of decursin increased as the stirring speed was increased to 200-250 rpm. Pearson's correlation indicated that the radical-scavenging activities using DPPH and ABTS assays were more sensitive to the Maillard reaction (R-2 = 0.822 and 0.933, respectively) than to the total phenolic contents (R-2 = 0.486 and 0.724, respectively). The extraction yield of decursin was higher when using conventional extraction methods than for SWE.