The adverse effects of 3 IGRs, 25% WP of diflubenzuron, 25% WP and 0.5% G of Bay SIR-8514, and EC-4 of MV-678, when evaluated for Chironomid control in a few experimental ponds, a sewage polishing pond, and a natural pond, were studied on the aquatic nontarget invertebrates. The WP and the G of SIR-8514 at 56 and 112 g AI/ha adversely affected Cyclops spp., Collembola, Chaoborus larvae, nymphs of Baetis sp., Notonecids and Corixids, and larvae of Coleoptera in the experimental ponds. Diflubenzuron at 28 and 56 g AI/ha reduced Cyclops spp., Collembola, Chaoborus sp. and Baetis sp. in these ponds but Cyclops spp. and Coleoptera showed more sensitivity to SIR-8514. The EC of MV-678 at 56 and 112 g AI/ha proved the least harmful of the 3 IGRs to the various invertebrates. In the sewage pond, SIR-8514 (WP) at 70 g AI/ha adversely affected Cyclops spp. and Hyalella azteca (Saussure). Cypridopsis sp. and Oligochaeta were not affected. The EC of MV-678 at 0.22 kg AI/ha no significant (P > 0.05) adverse effects on Diaphanosoma brachyurum (Lieven), Bosmina coregoni Baird, Ceriodaphnia sp., Diaptomus spp., Hydrachnellae, Hirudinea, and Oligochaeta in the natural pond.