This study describes the purification of an N-acetylglucosamine-binding lectin from Koelreuteria paniculata seeds and its effects on the larval development of Callobruchus maculatus and Anagasta kuehniella. The lectin (KpLec) was characterized and isolated by gel filtration, affinity column, and reverse phase chromatography. SDS-PAGE indicated that this lectin is a dimer composed of subunits of 22 and 44 kDa. The N terminus exhibited 40% similarity with Urtiga dioica agglutinin. KpLec was tested for anti-insect activity against C. maculatus and A. kuehniella. With regard to C. maculatus, an artificial diet containing 0.7 and 1% KpLec produced LD50 and ED50 value, respectively. However, for A. kuenhiella, an artificial diet containing 0.65% KpLec produced an LD50, whereas 0.2% KpLec produced an ED50. The transformation of genes coding for this lectin could be useful in the development of insect resistance in important agricultural crops.511029802986