Using the pea aphid, Acyrthosiphon pisum (Harris), as the host and Aphidius smithi Sharma and Subba Rao as the primary parasitoid, intraspecific tertiary parasitoidism was studied in the aphid hyperparasitoid, Asaphes lucens (Provancher). Laboratory experiments indicated that tertiary parasitoidism by a second A. lucens female on a first A. lucens is possible. Although the average success rate over 18 test-days was 16.9%, however, the day of attack by the second A. lucens female in reference to the age of the first A. lucens larva or pupa developing inside the dead aphid "mummy" was of major importance. Success by the second A. lucens in the early days averaged 27.2%, but was significantly reduced to an average of only 1% for the last 7 days. Comparisons are made with similar experiments on intraspecific tertiary parasitoidism using another aphid hyperparasitoid, Dendrocerus carpenteri (Curtis).