In the present study, we investigated the compositions, antioxidant activities and anti-tumor effects of Artemisia princeps Pampanini (APD) as well as blanched leaves (CNBD) and dried leaves (CND) from Cirsium setidens Nakai on HepG2 cells. Water and ash contents were increased in CND. Protein and lipid contents were increased in CNBD. K, Ca, Mg, Fe and Cu contents of CND were higher than those of CNDB and APD. P contents was significantly decreased in CND. Yields of CND was reached high levels, but TPC, TFC, acacetin, apigenin, cynarin contents, and antioxidant activity were higher in APD. Viability of HepG2 liver cells was significantly decreased in APD. Therefore, extracts of APD are more effective preventing the liver cancer than extracts of CND and CNBD.