Abstract: Cistoclemmys flavomarginata begins to lay eggs in late May with peak period in the middle of June.The incubation time is 46～54 days with spawning time at 18:00～21:00.They lay eggs once a year and the average annual is 2.5～2.6 with the fertilization rate of 64.0～64.6%.The incubation time is 76.7 and 75.8 days of fertilized eggs under the normal temperature incubation and constant temperature incubation.The shortest incubation time is 66 days and the longest incubation time is 82 days.The accumulated hatching temperatures are 47 491.2～57 741.1 ℃·h and 45 460.8～56 088.0 ℃·h.The average accumulated hatching temperature of normal temperature incubation is 1 803.8 ℃·h more than constant temperature incubation.The hatching rate of normal temperature incubation is 7.6% lower than constant temperature incubation.