Extraction methods of medicinal plants were evaluated for growth enhancing effects of human neuroblastoma SK-N-SH cells. Hot-water extraction (reflux for 5 hr), hot-water extraction post treatment (100℃ or 120℃, 90 min) and ethanol extraction (reflux for 5 hr) methods were applied to Angelica gigas, Rhemania glutinosa, Paeonia lactiflora and Cnidium officinale samples to extract their constituents. Cells were treated for 2 hr with various concentrations of extracts (0, 0.5, 1, 2, 4 ㎍/㎕ media) prior to H₂O₂ (250 μM) treatment for 2 hr to provide oxidative stress. Cell viability, caspase-3 expression and apoptosis were measured for cells treated with sample extracts. Hot-water extract exhibited a stronger growth enhancing and apoptosis protecting ability than other extracts. These activities were shown at less than 1 ㎍/㎕ concentration, and not greater than 2 ㎍/㎕ concentration. Hot-water extract contained more polyphenolic compounds than other extracts coming along with stronger antioxidant activity. The efficacy of antioxidant activity was stronger in the hot-water extract of Angelica gigas than other hot-water extracts of medicinal plants. These results suggest that hot-water extraction is an appropriate method to extract materials for growth enhancing and apoptosis protection of SK-N-SH cells, and hot-water extracts of Angelica gigas might be useful materials for protection from aging brain cells.