To understand the best formation and incubation condition of resting eggs produced by Brachionus urceus, we studied the formation and incubation of resting eggs on conditions of different light,temperature and the value of pH. Results showed that the incitement of the outer environmental factors are the main reason to induce gamogenesis. The yield of resting eggs is maximum, and the percentage of mix-mating female rotifers is the highest with pH 7.5 ; The hatch ratio of resting eggs is highest at 30 ℃ ; The light shine has no obvious influence ...