The present study was conducted to identify the distribution and changes of the glycoconjugates through the differentitation and maturation of tracheal mucosa of the Sprague-Dawley rat during pre- and postnatal development. During pre- and postnatal development of the tracheal mucosa of the rat, the distribution and change of the terminal sugars in the carbohydrate chains using lectin binding reactions were summarized as follows. 1) During prenatal development, the epithelial tissue was not reacted with lectins. 2) The glycoconjugates which contain β-(1-4)-D-N-acetyl-glucosamine, sialic acid, α-D-glucose, β-D-mannose, α-N-acetyl-galactosamine and β-D-galactose appeared in the epithelium of the tracheal mucosa of the rat from 1st day after birth and which contain α-D-manosyl, α-D-glucosyl, α-D-fucose and α-D-galactose appear from 3rd day after birth, respectively. 3) The glycoconjugates which contain α-D-glucose, β-D-mannose, β-D-galactose, α-D-mannosyl, α-D-glucosyl, β-(1-4)-D-N-acetyl-glucosamine and sialic acid appeared in the connective tissue matrix of the tracheal mucosa of the rat during all experimental period and which contain α-D-galactose, α-N-acetyl-galactosamine, galactose-β-(1-3)-N-acetyl-galactosamine, α-D-N-acetyl-galactosamine and α-D-fucose appeared from 19th day after birth, respectively. 4) The basement membrane was not reacted with lectins. Therefore authors judge that the continuous research toward basement membrane is needed.