The invasion of a potential parasitoid Pediobius foveolatus on the leaf miner Lithocolletis sp., which is a pest on Pongamia sp. tree was recorded during a field study carried out in north Delhi campus, during July to October for three years (2002-04). Pongamia sp. is a rich resource of bio-diesel. During these three years, Pediobius foveolatus had consistent occurrence and was recorded as ecto/endoparasitoid, solitary/gregarious, primary, larval and a koinobiont. Studies further revealed the egg or planidium stage of the parasitoid ectoparasitizing the tissue feeder of Lithocolletis sp. The parasitoid was observed as solitary and ectoparasitoid in July and August and gregarious and endoparasitoid in September and October for the three years. So far Pediobius foveolatus had been reported on the pest Epilachna sp. and Henosepilachna spp. Its presence on yet another pest host Lithocolletis sp. has been reported for the first time.