Abstract: Process for conditioning and preservation of eggs of oophagous parasites of insects, intended particularly to the biological combat against certain depredators of plants. According to this process, starting initially with eggs of lepidoptera of foodstuffs, particularly Iphestia Kuhniella, which have been previously conditioned, these eggs are then parasited by adults of Trichogrammidae, the parasited eggs are submitted to an incubation period, the incubated eggs are submitted to an induction period, and then the eggs thus obtained are cold-preserved. Application particularly to the biological combat against the pyralis of the Ostrinia nubilalis hubner corn.