Aims: To isolate a high b-glucosidase (BGL)-producing strain and to optimize BGL production in the isolated strain. Methods and Results: A high BGL-producing strain was isolated and identified as Fomitopsis pinicola KMJ812 based on its morphology and a comparison of sequence of its internal transcribed spacer rDNA gene. To increase BGL production, F. pinicola was supplemented with various vitamins. Supplementation with thiamine (20 mg l )1 ) improved BGL production in F. pinicola cultures by 3AE7-fold to give a specific activity of 114AE4 lmol min )1 mg )1 protein, one of the highest among BGL-producing micro-organisms. The increased production of BGL in the thiamine-supplemented culture was confirmed by 2D electrophoresis followed by MS ⁄ MS sequencing. The BGL purified from F. pinicola culture showed the highest catalytic efficiency ever reported. Conclusion: Supplemental thiamine remarkably increased BGL production by a novel BGL-producing strain, F. pinicola KMJ812.Significance and Impact of the Study: Our results provide a high BGL-producing strain and the production media for BGL production, and should contribute to better industrial production of glucose via biological processes.