To apply ELISA to serodiagnosis of leptospirosis with killed whole cells from Leptospira interrogans serovars mwogolo (Mwogolo), copenhageni (M-20), WH-20, autumnalis (Akiyami A), cynopteri (3522 C), australis (Bacillico) and Leptospira biflexa serovar patoc (patoc 1), sensitivity and specificity was evaluated. The reactivity of IgM and IgG antibody in the sera from patients with leptospirosis, hemorrhagic fever with renal syndrome and other febrile disease and normal healthy control to the killed whole cells was analysed. The results were summarized as follows. 1. The reactivity (absorbance at 492mn) of IgM and IgG to L. mwogolo antigen in the sera of pattients with leptospirosis were $1.414{pm}0.370$, $1.242{pm}9.554$ respectively: hemorrhagic fever with renal syndrome, $0.329{pm}0.131$, $0.239{pm}0.126$; other febrile disease, $0.196{pm}0.071$, $0355{pm}0.141$; normal healthy control, $0.136{pm}0.016$, $0.208{pm}0.077$. 2. The reactivity of IgM and IgG to L. copenhageni, WH-20, L. autumnalis, L. cynopteri and L. anstralis antigens were similar to that to L. mwogolo antigen, but that to L. biflexa antigen was not discriminated among above disease. 3. Correlation coefficient between the MAT titer and ELISA OD (IgM) to the above antigens was in the range of 0.071-0.518. 4. As absorbance above 0.60 was determined positive for the diagnosis of leptospirosis, the sensitivity and specificity of IgG was 25-89% and 91-96% respectively. And those of IgM was 98-100% and 89-100% except L. biflexa (29%) respectively.