A visit, from August 26 to Septermber 3, 2012, was head to the Pacific Basin Agricultural Research Center, U.S. Department Of Agriculture (USDA-PBARC). My objective for this visit was to acquire and deepen knowledge of biological controls over the oriental fruit flies (Bactrocera dorsalis).The USDA-PBARC has long been devoted itself to the intensive research into this. This time, I was mainly focused on the mass-rearing techniques and applications for two kinds of egg (Fopius arisanus) and larval (Diachasmimorpha longicaudata). The rearing actually progresses through four stages, from 1) parasitism, 2) pupation, 3)selection, to 4) emergence. From the experience on this visit, we could not only use native species in Taiwan, but also lend varieties to field controls of the oriental fruit flies. We could tackle them with releasing different parasitoids － combined with other chemical-free preventive practices － during their egg, larval, or pupae stages according to our demands. In this way, we could adopt an even more environmentally-friendly approach to effectively reducing the population of the oriental fruit flies.