AIM: To explore the mechanism of the mosquitocidal effect of Fendona. METHODS: The fourth instar larvae of Aedes albopictus were treated with different concent rations of Fendona (alphamethrin). The hemolymph was collected from early emerged female mosquitoes and then subjected to the detection of chemical elements and amino acids. The contents of elements including Fe, Zn, Cu, Cr, K, Na, Ca, Mg, S, P in three different concentrations (0.70, 1.39 and 2.79 μmol/L) of Fendona-treated groups and control group (0.2% acetone-treated) were compared. RESULTS: Compared to the control group, there was a significant increase in the contents of 8 kinds of elements except for Zn, Cr and Ca in the 2.79 μmol/L group; while in 1.39 μmol/L and 0.70 μmol/L groups, the contents of Fe, Mn, K and Mg were higher than those in the control group. Comparing the contents of 15 kinds of amino acids in hemolymph among 1.39 μmol/L, 0.70 μmol/L Fendona and the control group, the levels of 12 kinds of amino acids in Fendona groups were decreased. CONCLUSION: Fendona does influence the contents of many kinds of elements and amino acids in the hemolymph of adult Aedes albopictus.