Background: To prevent the recurrence of hydatid cysts after surgery, it is essential to use effective scolicidal agents. Most of these agents are not safe due to their undesired side effects. Recently, studies have been conducted to find natural scolicidal agents with more efficacies and low side effects. OBJECTIVES: In this study, the in vitro scolicidal effect of ethanolic extract of ginger (Z.officinale) on protoscolices of hydatid cyst was investigated. METHODS: A certain number of protoscolices (about 500) were treated with various concentrations of ginger ethanolic extract (40, 50, 100, 150 and 200 mg/ml) and the effect of each concentration was evaluated for specified time periods (15, 30, 45 and 60 minutes). Each concentration/time was performed in triplicate and the viability of protoscolices was confirmed by 0.1% eosin staining. RESULTS: The mortality rate with ethanolic extract of Z.officinale after 60 minutes was as follows:  68%, 92.3%, 93% and 100% at 50, 100, 150 and 200 mg/ml, respectively, and there was no significant difference between the three concentrations of 200, 150 and 100 mg/ml (P>0.05). However, at the concentrations of 200 mg/ml after 30 minutes of incubation, 100% protoscolices were dead. Based on Tukey’s test, a significant difference in the percentage of live protoscolices was found between the different concentrations of ginger extract with the exception of between 150 and 100 mg/ml concentrations (P>0.05). CONCLUSIONS: Ethanolic extract of Zingiber officinale had a high scolicidal activity in vitro, and it has the potential to be used as a scolicidal agent in the surgical treatment of hydatid cysts.