Objective : The main purpose of this study was to determine if Rehmanniae Radix has significant effects on lung fibrosis. Materials and Methods : C57BL/6J mice were devided into three groups. These were the normal group, which were not treated, the control group, given Intratracheal instillation(IT) of Bleomycin, the sample group, given IT of bleomycin and water-extracted Rehmanniae Radix. Animals were sacrificed 14 days after IT treatment. Lung fibrosis was evaluated by analysis of bronchoalveolar larvage(BAL) total WBC, percentage of macrophage, lymphocyte and neutrophil. This was done histologically by semiquantitative histological index(SHT) of lung tissue. Results : The sample group in coparison with control group showed a decrease in the BAL, total WBC, lower percentage of lymphocyte and neutrophil(p<0.05) and correspondingly a lower percentage of macrophage(p<0.01). The Sample group showed a significant decrease of collagen accumulation with respect to the control group in SHI of lung tissue(p<0.01). INF-${gamma}$ and IL-4 levels in BALF of mice significantly decreased in the control group(p<0.05). Conclusions : Results suggest that Rehmanniae Radix has an anti-imflamatory effect and anti-fibrotic effect on the lungs through decrease of IL-4 and total WBC count for not only macrophage, but also lymphocyte and neutrophil. The degradation of INF-${gamma}$ calls for research beyond the scope of this study.