Abstract: Several digestive enzyme activities of the rotifer Brachionus plicatilis during starvation and refeeding were studied under 25℃. The results showed that activities of amylase and cellulose maintained high lever during the whole process. During starvation, activities of amylase and cellulose decreased dramatically in the first two days, and then maintained stable, while activities of pepsin and tryptase decreased slowly. When egg ratio was less than 0.09, all four digestive enzyme activities were lower than the compared. After one-day refeeding, egg ratio increased from 0 to 0.21, activities of tryptase and cellulose increased to normal level, and activities of pepsin and amylase were higher than the compared. Stomach and gastric glands restored normal after one-day refeeding in vivo observation. It was found these four digestive enzyme activities were not related with the egg ratio when rotifer was fed.