This study was investigated antioxidant and anticancer activity of water, methanol extract from upper and root part of Taraxacum mongolicum H. Total phenolic compound contents of methanol and water extracts from upper part were $51.95{pm}0.18$ mg/g and $48.16{pm}0.89$ mg/g respectively, and total flavonoid compound contents were estimated as $20.57{pm}1.12$ mg/g in methanol extract and $6.55{pm}1.20$ mg/g in water extract. $EC_{50}$ values for DPPH radical scavenging activity of methanol and water extract from upper part were $138.47{pm}3.78{mu}g/mL$ and $204.38{pm}5.32{mu}g/mL$, and methanol and water extracts from root part were as $512{pm}8.11{mu}g/mL$ in methanol extract and $1315.05{pm}11.98{mu}g/mL$ in water extract. Reducing power and hydroxyl radical $({ullet}OH)$ scavenging activity estimated that methanol extract of each part were higher than water extracts. The cell viability showed that the methanol extract from upper part had a cytotoxicity in the growth of colon carcinoma cell (44.58%). Both water extract $(51.97{pm}11.43%)$ from upper part and methanol $(53.46{pm}19.77%)$, water $(52.79{pm}13.53%)$ extracts from root part had quite higher cytotoxicity than that of methanol extract $(88.25{pm}2.02%)$ from upper part. Based on the results, It was suggested that the methanol extract of Taraxacum mongolicum H. were potential materials for use as functional food and medicine.