Continuous preparation of theaflavins by immobilized polyphenol enzyme in packed bed bioreactor were performed in this paper and The apparatus of continuous preparation system was designed and maded by ourself.In this study,we used D152(macroreticular weak acidic acrylic acid cation exchange resin) as a matrix to immobolize laccase extracted from Trametes spp.Then we utilized this bio-materials to transformat tea catechins into theaflavins consecutively in a packed bed reactor.Four mainly facts were considerated in this experiment as following: temperature,substrate flow ratio,oxygen flow rate,pH and subsrate concentration.As a results,we selected the temperature at 28℃,substrate flow ratio 2.0 mL/min,oxygen flow rate 55 mL/min,pH 5.7 and substrate concentration 10mg/ mL as a optimized condition to biosynthesize theaflavins at a highly efficient.This experiment conditions will give a reference for large scale producing theaflavins basically.