Various sterilization methods were applied to the powder of ginseng for the improving hygienic quality. Ultra-violet (UV) and Infrared ray (IR) treatments could not inhibit highly growth of bacteria in ginseng powder. However, high hydrostatic pressure treatment showed high inhibition rate against bacterial growth in ginseng powder. Changes of viable cell count by the pressure showed positive relationship between growth inhibition rates and the pressures applied. When powder was treated with 2,000 kg/㎠ for 10 min at 25℃, initial viable cell count of the powder, 2.0 × 10⁴ CFU/g, was decreased to 1.0 × 10⁴ CFU/g. When it treated with 3,000, 4,000 and s,000 kg/㎠ of pressures under the same condition, viable cell counts were 8.0 × 10³, 7.0 × 10³ and 1.8 × 10³ CFU/g, respectively. Ginseng saponins of the powders were all detected when analyzed by TLC chromatography after treatment with the pressures. Therefore, it was considered that saponin of ginseng powder was stable under the condition of 5,000 kg/㎠ of pressure, even though the treatment induced coagulation of the powder.