To investigate anaesthetic and some hematological effects of clove oil and eugenol for European eel, Anguilla anguilla, L., 1758, 0.0, 0.025, 0.05 and 0.075 ml/l of clove oil or 0.0, 2.250, 3.375 and 4.500 ml/l of eugenol were applied to fish (80.95 +/- 8.94 g). After fish was anaesthetized, half of fishes from each group were transferred into recovery tanks (to clean water), whereas, other half was retained there for next 48h. Induction time ranged between 3 and 5 min for clove oil and 2 and 5 min for eugenol. Fish reached to 5(th) anaesthesia stage in all experimental groups except control and the lowest concentration group of both anaesthetics. Reaching the fish to 8(th) stage of recovery took 60 min in all groups. Opercular rates of fish in test groups of clove oil and eugonal decreased slightly. During the study no mortality was observed. WBC counts decreased (P < 0.05), but RBC counts, hematocrit value and glucose level increased by increasing dose (P < 0.05). It is conclused that 0.050 ml/l of clove oil or 3.375 ml/l of eugenol can be accepted suitable to anaesthetize European eel of this size.