Abstract: OBJECTIVE To observe the in vitro activity of Ranunculus Ternati Radix saponins(RRTS) on non-small cell lung cancer(NSCLC) cell of NCI-H460. METHODS Ranunculus Ternati Radix saponins was extracted by the technique of solvent-refining. Effect of different concentrations of Ranunculus Ternati Radix saponins on cell NCI-H460 were tested by ³H-TdR incorporation method. The cell cycle phase and apoptosis were inspected by flow cytometry. RESULTS The results showed that RRTS could inhibit the growth of NCI-H460 cell, showing a dose-effect curve. It could also promote the early apoptosis of cell NCI-H460 and arrest the cell cycle in G₀/G₁ phase. CONCLUSION Ranunculus Ternati Radix saponins can inhibit the proliferation of cell NCI-H460, its mechanism is probably related to apoptosis induction and blockage of cell cycle in G₀/G₁ phase.