Effect of liming material application on the prevention or cure of Mn toxicity symptoms including marginal leaf chlorosis in 3-year-old ginseng plants grown in acidic soils were investigated. It was found that the ratio of Fe to Mn was above about 0.5 and the ratio of Mn to Fe was below about 2.00 in 4-year old ginseng leaves when liming materials were applied in field experiments. It was apparent that the occurrence of marginal leaf chlorosis was decreasing affected by application of Ca, Mg and Fe. The appearance of marginal leaf chlorosis was decreased to about 78 percent in 4-year-old ginseng and to about 69 percent in 5-year-old ginseng, and then the fresh root weight was increased up to 66 percent in 4-year ginseng plants.