Abstract: A black tea flavor suspended drink containing konjac glucomannan/konjac oligosaccharides was prepared with the addition of konjac glucomannan, hydrolysised konjac glucomannan by β-glucan, and instant black tea powder.On the basis of single factor experiment, the orthogonal experiment was used to optimize the enzymatic hydrolysis conditions.The results showed that the hydrolysis rate and the viscosity for the hydrlysate were 50.4% and 14.3mPa·s separately at the condition of the konjac glucomannan concentration 25% (W/W) , dosage of enzyme 150U/g, pH 5.5, temperature 45℃, time 600s.The recipe for the sugar-free suspended drink were:xylitol 10%, citric acid 0.15% and agar 0.1%, CMC 0.1%, hydrolysate 0.9% and konjac glue 0.3%, instant tea powder 0.15%.