The tendency of immune response toward either Th1 or Th2 cytokine pattern can cause a number of pathologic conditions. Multiple sclerosis is postulated to be a Th1-type cell-mediated autoimmune disease. MS14--an Iranian natural product--seems to possess anti-inflammatory properties. Thus, we studied the effect of orally administered MS14 on Th2 cytokines (IL-5 and IL-10) in normal Balb/C mice (100 mg/kg; 5 days). The result indicated that activated splenocytes of MS14 group produced significantly more IL-5 and IL-10 (3-4 times in comparison with control group mice). MS14 could upregulate Th2 cytokine and thereby it may possess immunoregulatory properties probably useful in treatment of some diseases.