Koinobiont and solitary, early instar larval endoparasitoid. Apanteles galleriae Wilkinson were reared on two lepidopterous host species, the greater wax moth, Galleriae mellonella (L.) and the small wax moth. Achoria grisella Fabr. under a photoperiod of 12:12 h (D: L) at 25°C and 60% relative humidity. The parasitoid with three larval instars completed its immature developmental period within 26-28 days when it was reared on G. mellonella and within 25-27 days on A. grisella. The adult parasitoid has no preoviposition period. In the first 24 hours of the adult female life span. 10 to 20 eggs were laid. The duration of oviposition of the females was 3-8 seconds. Adult males and females were able to mate soon after the emergence, and the average duration of copulation was about 23 seconds. The adult size of the parasitoid was variable depending on the host. The adult life span of the parasitoid was also variable depending on the sex of the individual and whether or not it had mated. Adults that had mated lived longer than those that had not, and male adults lived longer than females. Seasonal variation was found in the adult life span of the parasitoids. It is recorded that the host species and the number of parasitoids tested affected the host preference of the parasitoid. A. galleriae preferred A. grisella to G. mellonella as a host.