Abstract: 4-methyl-5-（β-hydroxyethyl）-thiazole was prepared, starting from α-acetobutyro-lactone, by chloronation, hydrolysis and decarboxylation, cyclization, diazotization and reduction. The yield of diazotization and reduction was remarkably increased and the procedure was simplified by the use of H₂SO₄ in place of HCl, thus avoiding the formation of the by-product （2-chloro-4-methyl-5-（β-hydroxyethyl）-thiazole,） and finished the preparation of the object product in a one pot process. The total yield reached 70%.