The immunomodulatory effect of a new herbal preparation, HemoHIM, on the recovery from leukopenia induced by cyclophosphamide treatment was investigated. The HemoHIM was made up with an addition of the ethanol-insoluble fraction to the total water extract of Angelica Radix, Cnidii Rhizoma and Paeonia Radix. Daily oral administration of 100 mg/kg BW or 500 mg/kg BW HemoHIM accelerated the recovery from cyclophosphamide-induced leukopenia. HemoHIM increased the number of leukocytes and lymphocytes in the peripheral blood when compared with the cyclophosphamide-treated control. Moreover, the suppressed natural killer (NK) cell activity and interferon $(IFN)-{gamma}$ secretion in the cyclophosphamide-treated mice were restored by the administration of HemoHIM. HemoHIM significantly reduced the abnormally heightened ratio of interleukin $(IL)-4/IFN-{gamma}$ and immunoglobulin (Ig)E/IgG2a in the cyclophosphamide-treated mice. These results suggest that HemoHIM accelerates the recovery from leukopenia and alleviates the imbalanced T helper (Th)l/Th2 responses in the cyclophosphamide-treated mice. Additionally, HemoHIM was found to stimulate normal splenocytes to secrete not only Thl type cytokines such as $IFN-{gamma}$ and IL-2, but also Th2 type cytokine IL-4. In conclusion, our results show that HemoHIM certainly has an influence on the balanced recovery of immune cells and the activation of their activities in the cyclophosphamide-treated mice.