Abstract: The supernatant of protective McAb (isotype IgG2a) secreted by 1E2 hybridoma line was purified by protein A-sepharose CL-4B column and rabbits were immunized with purified 1E2 McAb. Dot-ELISA, immunodiffusion assay, Western blotting and ELISA were used to observe the presence of anti-McAb and anti-anti-McAb. The main results are: 1. anti-McAb antibody could be detected as early as 20 days post immunization in the immune sera and would be decreased gradually without boosting; otherwise, it would be increased quickly and the liters of anti-McAb were increased within 5 days postboosting and could be maintained at a plateau for 30-50 days, and then decreased gradually to the normal; 2. there were different anti-anti-McAbs in the immune sera. Anti-anti-McAb, like anti-anti-idiotype antibody, can recognize different schistosome antigens and 90, 68 or 45 kDa antige.nic determinants. The level of anti-anti-McAbs varied from tilers 1:100 to 1:1 600 at different time post-immunization with 1E2. The results provide evidence to understand the appearance of anti-McAb antibody and the way to develop anti-idiotype and anti-anti-idiotype McAb for research purpose.