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The red imported fire ant (RIFA) Solenopsis invicta Buren causes severe damage to humans and animals as well as the environment.Chemical treatment, which is potentially toxic to the environment, is the main strategy of RIFA management.Plant essential oils are considered a potential substance that can be used to control insects.The present study aimed to identify the chemical composition of camphor essential oil and investigate the insecticidal activity on RIFAs.The chemical composition of the essential oil was analyzed by GC-MS and GC-FID.Results revealed 36.61% camphor and 30.05% cineole as major components.The insecticidal activity of camphor oil was assessed against RIFA workers by conducting two different bioassays: fumigant toxicity and repellence.Fumigant toxicity assay results showed that the lethal dose (LD50) of the essential oil at 24 h was 1.67 and 4.28 tg/mL for minor and major workers, respectively; knockdown time (KT50) was 10.82 and 14.73 h.At 2.55 tg/mL,the highest average mortality of the ants was 84.89% after 72 h.Camphor essential oil exhibited fumigant toxicity against minor and major workers as indicated by the effects on attacking, feeding, and climbing behaviors.This essential oil was also strongly repellent to the two members of colonies as observed in their behavior against Tenebrio molitor treated with 5 μL essential oil.The fumigant toxicity and repellence of camphor essential oil against RIFA indicated that this substance could be a potential alternative for the development of eco-friendly products used to control pests.