Schistosomiasis haematobium is a serious public health problem inEgypt. Detection of S.haematobium antigens is a betterimmunodiagnostic tool than determination of the antibody level. In thisstudy sandwich ELISA was used to detect L cathepsin antigen in bothserum and urine samples of humans. A comparative evaluation of theperformance of L cathepsin was performed in relation to two otherantigens; crude worm antigen and soluble egg antigen. Detection of Lcathepsin in serum gave a sensitivity of 95%, a specificity of 93.7%compared to other parasitic infections group and 100 % compared tohealthy control group. On the other hand, detection of L cathepsin inurine gave a sensitivity of 91%, a specificity of 93.7% compared to otherparasitic infections group and 100% compared to the healthy controlgroup. L cathepsin OD value correlates significantly with infectionintensity.