Timor deer (Cervus timorensis) at Surabaya zoo, Indonesia, that were found to be naturally infected with Fasciola, showed elevated level of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). Of a total of 75 deer examined, 12 (25%) of the 47 adult deer and 8 (29%) of the 28 juvenile deer were found to be infected with fascioliasis, as evidenced by the shedding of the parasite eggs. The level of ALT, AST and ALP were significantly elevated (p<0.05) in all the infected deer. Only Fasciolainfected deer showed elevated serum liver enzyme. Deer with elevated enzyme level show a trend that positively correspond with higher Egg per gram of feces (EPG). The average size of the parasite eggs at 169.0±11.1 × 96.0±3.5μm, correspond well with that of Fasciola gigantica. No other trematode eggs were observed besides that of F. gigantica. There was no significant difference in the enzyme profile between the two sexes in both the infected and the uninfected group. This is the first report of the elevation of serum liver enzyme in Timor deer that is associated with not only fascioliasis and also correspond positively with the EPG.