Purpose: The purpose of this study is to investigate the effect of Boheo-tang (B) and Boheo-tang plus cervi pantotrichum cornu (B+CP) on lactation in postpartum C57BL/6N mice. Methods: Normal saline(control), Band B+CP (8mu l/g$) were administerd p.o. twice a day for 20 days. Lactating mammary gland tissues were examined through light microscope by the way of HE staining and immunohistochemical assay. Milk producing associated gene expression were accessed by RT-PCR. Results: In mammary gland, amount of adipose tissues were decreased in both Band B+CP treated group. And the ductal branches and alveolar tissues increased in both treated group. Immunoreactivity of prolactin receptors was increased both treated group, and immunoreactivity of oxytocin receptors was increased in the B+CP treated group. In both treated group, IGF-l mRNA expression was increased and TGF-$eta$ mRNA expression was decreased. And PRL mRNA expression was increased in the B+CP treated group. PL-l mRNA expression was decreased in the B treated group but increased in the B+CP treated group. Conclusion: This study shows that treatment of Boheo-tang and Boheo-tang plus cervi pantotrichum cornu can improve postpartum lactation in C57BL/6N mice.