Ripe fruit of Maclura tricuspidata has been traditionally used as a raw material for the preparation of fermented foods such as wine and vinegar in Korea. This studies were carried out to investigate changes of nutritional (soluble solids, free sugars and free and total amino acid composition) and bioactive constituents (phenolic compounds and parishin derivatives) during the liquid fermentation of M. tricuspidata fruits with Armillaria mellea (honey mushroom). The soluble solid, free sugars and free amino acids were gradually decreased during fermentation while meaningful changes of pH and total amino acids did not observed even after 10 day fermentation. The content of phenolic acids, particularly chlorogenic acid and parishin derivatives were decreased while that of caffeic acid and 4-hydroxybenzyl alcohol (4-HBA) were increased during the 10 day fermentation period. The crude enzyme preparation from liquid culture of A. mellea biotransformed parishin A into 4-HBA via parishin B, parishin C and gastrodin with high transformation ratio. Based on the results above, we discovered that parishin A and its derivatives are transformed into 4-HBA via parishin B, parishin C and gastrodin by esterase and β-glucosidase secreted by the mushroom mycelia during fermentation.