Definition of delayed interval delivery (DID) in multiple pregnancy is that in the middle pregnancy, especially when gestational age ≤ 24-week, after the abortion or preterm delivery of one of the fetuses (fetus 1) among multiple pregnancy fetuses, the uterine contraction of pregnant women gradually decreases, the uterine orifice gradually retracts, and even cervical canal is closed. If intervention measures are taken in time, the other fetuses can remain in the uterus of pregnant women for several days or even several weeks, and then be delivered after the organs of remaining fetuses being more mature. Due to the increasing of women′s conceptional age and the application of assisted reproductive technology, the occurrence rate of multiple pregnancy has increased gradually. After the abortion or preterm delivery of fetus 1 among multiple pregnancy fetuses, the success rate of DID for the remaining fetuses is also increasing. The indications of DID in multiple pregnancy including: uterine contraction decrease or disappear without premature rupture of membrane (PROM), chorioamnionitis, serious vaginal bleeding, suspected placental abruption or serious complications diseases of internal medicine or surgery of the patients, no intrauterine distress or congenital malformation in the fetus. At present, the clinical treatment measures of DID included ligation of the umbilical cord of the expelled fetus as high as possible, prophylactic use of tocolytic for inhibition of uterine contraction and antimicrobial agents for infections, cervical cerclage and continuous monitorization of the patient, and useing glucocorticoid to promote fetal lung maturity if necessary. It is very important to determine the delivery time after DID for the remaining fetuses. This article focuses on the latest research progresses on necessity, applicable population, clinical management, clinical processes and pregnancy outcomes of DID fetus in multiple pregnancy, in order to provide reference for related clinical research of DID in multiple pregnancy.