The ecto-parasitoid, G.legneri, was reared in the laboratory on lar­vae of the navel orangeworm, Amyelois transitella (Walker). At 27±1 °C and 50-55% R.1-1., the egg-incubation period was 24 hrs, the larval stage lasted 3.1 days, the pre-pupa lasted 26 hrs and the pupa lasted 6.7 days. The total developmental period of the parasitoid averaged 11.3 days. G.legneri females did not deposit eggs daily and the number of egg-deposition averaged 21.5 times during her life-span which averaged 69A days. The number of eggs deposited each time averaged 13.4/ female and the total number of eggs deposited/female averaged 260.8. Two trials of rearing were tested for mass production of the par­asitoid with the aim of utilizing it as a biocontrol agent in the field.