This study aimed to evaluate the effects of extraction parameters on the total saponin and polysaccharide contents of Vietnamese ginseng extract collected in Tuyen Quang province. One-year-old ginseng roots were ground to a particle size of ≤ 1.5 mm and extracted under heat using an ethanol–water solvent system. The effects of extraction time, ethanol concentration, extraction temperature, and material-to-solvent ratio were initially investigated and subsequently optimized using an experimental design implemented in MODDE 4.0 software. The results indicated that extraction equilibrium was achieved after approximately 3–4 hours. Ethanol concentrations of 50–60% and extraction temperatures ranging from 50 to 65°C provided high extraction efficiency. The optimal extraction conditions were determined to be 66°C, 54.6% ethanol, and an extraction time of 1.32 h (three extraction cycles: 80 min for the first extraction and 35 min for each of the subsequent two extractions). These findings contribute to the development of a preparation process for Vietnamese ginseng liquid extract and provide a scientific basis for the development of pharmaceutical products derived from this medicinal plant.