Siberian ginseng (Eleutherococcus senticosus) is used primarily as an adaptogen herb and also for its immunestimulant properties in Western herbal medicine. Another closely related species used in East Asian medicinesystems i.e. Kampo, TCM (Manchuria, Korea, Japan and Ainu of Hokkaido) and also called Siberian ginseng(Acanthopanax senticosus) also displays immune-stimulant and anti-cancer properties. These may affect tumourgrowth and also provide an anti-fatigue effect for cancer patients, in particular for those suffering from lungcancer. There is some evidence that a carbohydrate in Siberian ginseng may possess not only immune stimulatorybut also anti-tumour effects and also display other various anti-cancer properties. Our study aimed to determinethe inhibitory and also proliferative effects of a methanol plant extract of Siberan ginseng (E. senticosus) onvarious cancer and normal cell lines including: A-549 (small cell lung cancer), XWLC-05 (Yunnan lung cancercell line), CNE (human nasopharyngeal carcinoma cell line), HCT-116 (human colon cancer) and Beas-2b (humanlung epithelial). These cell lines were treated with an extract from E. senticosus that was evaporated and reconstitutedin DMSO. Treatment of A-549 (small cell lung cancer) cells with E. senticosus methanolic extractshowed a concentration-dependent inhibitory trend from 12.5 - 50μg/mL, and then a plateau, whereas at 12.5and 25 μg/mL, there is a slight growth suppression in QBC-939 cells, but then a steady suppression from 50, 100and 200μg/mL. Further, in XWLC-05 (Yunnan lung cancer cell line), E. senticosus methanolic extract displayedan inhibitory effect which plateaued with increasing dosage. Next, in CNE (human nasopharyngeal carcinomacell line) there was a dose dependent proliferative response, whereas in Beas-2 (human lung epithelial cell line),an inhibitory effect. Finally in colon cancer cell line (HCT-116) we observed an initially weak inhibitory effectand then plateau.