Culex pipiens Linnaeus, 1758is the chief vector of dangerous diseases such as lymphatic filariasis in tropic and subtropic regions. The current study aimed to investigate the larvicidal effect of nanoemulsion of Pimpinella anisum L. essential oil by studying the associated cuticular deformations in Culex pipiens larvae via scanning electron microscopy. The nanoemulsion was prepared using ultrasonication method. The mean droplet size of the nanoemulsion was 116nm, with poly dispersity index equal to 0.21. The LC₅₀ of the nanoemulsion was 40.1ppm. The third instar larvae were treated with the LC₅₀ of the prepared nanoemulsion. The cuticular deformations possibly inhibited the ability of the larvae to continue developing leading at the end to the death of these treated larvae. This is the first report to demonstrate the association between the nanoemulsion of Pimpinella anisum and the cuticular changes of Culex pipiens larvae. The results of the present study proved that nanoemulsion of Pimpinella anisum EO can be considered as a promising candidate in the integrated management programs to control Culex pipiens.