Naturally occurring glycoproteins have been extracted from fundic and antral mucosal tissue of the hog stomach by means of nondegrading techniques. Major and retarded glycoprotein fractions separated by gel filtration were further dissociated from appreciable amounts of noncovalently bound proteins by CsCl density gradient centrifugation. Antisera to glycoprotein fractions of fundic and antral regions of the stomach were prepared in rabbits. The major fractions from both gastric regions have similar molecular mass (∼2 × 106), sedimentation coefficient (∼31.5 s), and specific viscosity (∼1.6). Purified fractions from each region were further separated into two subfractions by affinity chromatography on wheat germ lectin. Clycoprotein subtractions from antrum and fundus differ appreciably in their carbohydrate and am/no acids content, share antigenic determinants, but do not cross‐react with anti‐hog serum protein anti‐sera. Further diversity in native mucin glycoproteins was observed by the use of one‐(D) and two‐dimensional (2D) immunoelectrophoresis; subtractions that cross‐react with specific anti‐hog gastric glycoproteins were found to contain three or more components.