Bauhinia variegata var. variegata seeds are rich in proteins. Previously, one of the major storage proteins of the seeds was found to be a trypsin inhibitor that possessed various biological activities. By using another purification protocol, a glucoside- and galactoside-binding lectin that demonstrated some differences from the previously reported B. variegata lectin could be isolated from the seeds. It involved affinity chromatography on Affi-gel blue gel, ion exchange chromatography on Q-Sepharose and Mono Q, and also size exclusion chromatography on Superdex 75. The lectin was not retained on Affi-gel blue gel but interacted with Q-Sepharose. The lectin was a 64-kDa protein with two 32-kDa subunits. It had low thermostability (stable up to 50 A degrees C) and moderate pH stability (stable in pH 3-10). It exhibited anti-proliferative activity on nasopharyngeal carcinoma HONE1 cells with an IC50 of 12.8 mu M after treatment for 48 h. It also slightly inhibited the growth of hepatoma HepG2 cells. The lectin may have potential in aiding cancer treatments.