The analysis of condensation and cleavage reaction was carried out at 30℃ and pH 7.0 with purified isocitrate lyase from Saccharomycopsis lipolytica ATCC 44601. The Km values for condensation reaction. of glyoxylate and succinate were 0.06 and 0.21 mM, respectively. In the cleavage reaction, glyoxylate was a linear competitive inhibitor with a Ki of 0.22 mM and succinate was a linear noncompetitive inhibitor with a Ki of 0.82 mM. Therefore, these kinetic analyses showed that the enzyme functioned in a ordered reaction with glyoxylate binding before succinate in the condensation reaction. 3-Bromopy-ruvate(BrP) was found to be irreversibly inactivation showing saturation kinetics, the inactivation half-time was 0.15 min and K_(BrP), was 0.032 mM, and substrate or reactant protected against the inactivation.