In fascioliasis, T-helper 2 (Th2) responses predominate, while little is known regarding early immune phenomenon. We herein analyzed early immunophenotype changes of BALB/c, C57BL/6, and C3H/He mice experimentally infected with 5 Fasciola hepatica metacercariae. A remarkable expansion of $CD19^+$ B cells was observed as early as week 1 post-infection while $CD4^+/CD8^+$ T cells were down-regulated. Accumulation of $Mac1^+$ cells with time after infection correlated well with splenomegaly of all mice strains tested. The expression of tumor necrosis factor (TNF)-${alpha}$ mRNA in splenocytes significantly decreased while that of IL-4 up-regulated. IL-$1{eta}$ expression was down-modulated in BALB/c and C57BL/6 mice, but not in C3H/He. Serum levels of transforming growth factor (TGF)-${eta}$ were considerably elevated in all mice during 3 weeks of infection period. These collective results suggest that experimental murine fascioliasis might derive immune suppression with elevated levels of TGF-${eta}$ and IL-4 during the early stages of infection.