Abstract: Sand water content had the serious influence on the survival of larvae and one-day-old pupae of oriental fruit fly,Bactrocera dorsalis.Excessive water loss was an important reason,could cause the prepupation and pupal mortality.In the desiccation condition,only 11.67% of the 3~(rd) instar larvae could survive and develop to emerge.The mortality of oneday-old pupae kept inside a desiccation container for 9 days reached to 75.47%.Under the saturated moist condition,none of larvae and pupae could survive.It was indicated that high sand water content had a negative effect on the pupae. The survival rates of three-day-old and six-day-old pupae were 39% and 41% respectively under the high sand water content condition(RH 80%).And the abnormal rates of adults and six-day-old pupae were significantly high under the condition of desiccation and high sand water content.