Large quantities of lectin were extracted from Florunner peanut seeds and purified by affinity chromatography. The purity and biochemical properties of this lectin were comparable to commercially prepared peanut lectin (Sigma Chem. Co.). These were evidenced by monitoring hemagglutinating activity, UV absorption spectra, absorbance ratio at 280 nm and 260 nm, extinction coefficient, disc gel electrophoresis and subunit molecular weight determinations.