AIM: To study the usefulness of 18 kDa/16 kDa antigens in larval Echinococcus multilocularis, designated E. m. 18 kDa and E. m. 16 kDa, for immunodiagnosis of human alveolar echinococcosis. METHODS: Western blot analysis based on the detection of antibody responses against E. m. 18 kDa and E. m. 16 kDa and commercially available E. m. 2-ELISA were evaluated comparatively using 24 sera from patients with alveolar echinococcosis, 55 sera from patients with cystic echinococcosis, 33 sera from patients with cysticercosis and 30 sera from healthy controls. RESULTS: All 24 (100% ) sera from alvrolar echinoco-ccosis patients recognized both E. m. 18 kDa and E. m. 16 kDa in Western blotting, whereas 23 of them were positive in E. m. 2-ELISA. The cross-reactivity with sera from Cystic echinococcosis was 16.4% for E. m. 18 kDa, 29.1% for E. m. 16 kDa and 23.6% for E. m. 2, while the cross-reactivity with sera from Cysticercosis was 3.0% for E. m. 18 kDa, 33.3% for both E. m. 16 kDa and E. m. 2. None of the sera from healthy controls showed reactivity with E. m. 18 kDa, E. m. 16 kDa or E. m 2. CONCLUSION: Our findings confirmed the high potential of E. m. 18 kDa and E. m. 16 kDa for immunodiagnosis of alveolar echinococcosis, and E. m. 18 kDa in particular.