Artificial eggs were treated with ethanol-extracted kairomone to induce oviposition for in vitro rearing of Ooencyrtus kuvanae. Oviposition behavior and emergence pattern of in vitro reared parasitoids were investigated to be compared with those of in vivo strain. Total developing periods of O. kuvanae from egg stage until emergence were 15$pm$1 days in in vitro and 14$pm$1 days for those reared in in vivo. Parasitism on gypsy moth egg masses by in vitro strain within 24 hours in a screen cage (40$ imes$40$ imes$40cm) was lower compared with in vivo strain and in the case of 10 parasitoids per cage, parasitism rate was 3.4% which was one third compared with 9.0% in in vivo strain. However, the mean numbers of parasitoids per a host egg were not much different between them, and the sex ratio (♂:♀) were a little lower in in vitro strain than the other. Host acceptance behaviors of adult females from both strains were initiated immediately after emergence and the numbers of ovipositing female continuously increased until 7th day. However, the ovipositing activity of in vitro strain was less active than that of the in vivo strain. Successful ovipositing of in vitro strain was initiated from the 3rd day after emergence and oviposition increased up to the 7th day. The highest oviposition rate was observed in the 7th day in vivo strain and oviposition was initiated from the 2nd day after emergence. Adult emergence from the artificial eggs started 14 days after oviposition and continued up to the 26th day with the peak at the 16th day.