The aim of this study was to evaluate the long-term effects of the insecticide acetamiprid on the parturial moulting and reproduction of the terrestrial isopod Armadillo officinalis. Adult woodlice were exposed to acetamiprid at 0.05, 0.1, 0.2, 0.4 mg/kg of dry soil. During 100 days of exposure, the effects on parturial moult and reproduction were investigated. The preparturial intermoult, the parturial premoult and the ecdysis stages were followed, and their duration was calculated. Also, an assessment of reproductive impairment was carried out using the following parameters: percentage of gravid females, incubation period length and the number of mancas released. The results showed that the exposure to acetamiprid significantly impaired the parturial moult in Armadillo officinalis. Indeed, it prolonged preparturial intermoult duration at the concentrations > 0.1mg/kg soil and prolonged parturial premoult and ecdysis duration at all tested concentrations. Furthermore, the results demonstrated that acetamiprid significantly impaired the reproduction of Armadillo officinalis. It decreased the percentage of gravid females at the highest concentration (0.4 mg/kg) and reduced the number of mancas released at all tested concentrations. These results raise concern about long-term effects of acetamiprid on terrestrial isopods’ populations and suggest that acetamiprid could also pose a potential risk to other beneficial soil organisms and consequently reduce soil fertility.