Lectin histochemistry is a useful technique to identify and to localize in cells and tissues the terminal carbohydrate moieties of glycoproteins and glycolipids. The specific diagnosis of some glycoprotein storage diseases was accomplished using lectin staining patterns, and such methods of diagnosis have been attempted for some glycolipid storage diseases. This technique was applied to formalin-fixed paraffin-embedded and frozen neural, hepatic, and renal tissues of sheep with an inherited lysosomal storage disease with deficiencies of beta-galactosidase and alpha-neuraminidase. The cytoplasm of central nervous system neurons of affected sheep in paraffin-embedded sections stained with peanut agglutinin (PNA), Ricinus communis agglutinin-I (RCA-I), Dolichos biflorus agglutinin (DBA), and soybean agglutinin (SBA). The cytoplasm of neurons in frozen sections of these tissues stained with PNA, RCA-I, wheat germ agglutinin (WGA), and Ulex europaeus agglutinin-I (UEA-I). The cytoplasm of frozen and paraffin-embedded sections of liver and kidney of affected sheep stained with PNA, whereas paraffin-embedded sections also stained with RCA-I. These results suggest the stored material in this disease has terminal saccharide moieties consisting of beta-galactose, N-acetylneuraminic acid, and N-acetylgalactosamine. Paraffin processing altered lectin staining patterns. Although the staining pattern in this glycolipid storage disease was complex, lectin histochemistry may prove to be a useful technique for the characterization of storage products and for the diagnosis of lysosomal storage diseases.