Six hundred strains of soil microorganisms were screened for the production of hydroquinone glucosylating enzyme (HGE). One of these strains, Bacillus subtilis strain X-23, produced an enzyme that glucosylated hydroquinone in the culture filtrate. The HGE was successively purified by ammonium sulfate fractionation, and Q-Sepharose, Phenyl-Toyopearl, and Superose 12 column chromatographies. The molecular weight was estimated as 65 kDa by SDS-polyacrylamide gel electrophoresis, and 54 kDa by gel filtration. Based on an analysis of the hydrolytic products from soluble starch, HGE was considered to be a kind of alpha-amylase. The structure of the hydroquinone glucoside produced by HGE was identified as 4-hydroxyphenyl-O-alpha-D-glucopyranoside by alpha- and beta-glucosidase treatments, and H-1-NMR and C-13-NMR.