Human echinococcosis is one of the world's major zoonotic infections. In this study, our aim is to clarify one of the strategies used by the parasite for evasion and prolonged infestation in the host. We wished to provide further immunological evidence for the involvement of IL-10/IL-4 in these mechanisms. In this regard, we investigated the effects of IL-4 and IL-10 on protoscoleces (PSC: the larval form of the parasite), co-cultured with patient PBMC. Furthermore, we used IL-4 and IL-10 antibodies to confirm this effect. Our results showed that IL-4 and IL-10 reduced PSC killing. This reduction correlates with an decrease in NO production by PBMC. In conclusion, the results reported here suggest that IL-4/IL-10 impairs the Th1 protective response and allows the parasite to survive in hydatid patients.