Schistosomiasis is one of the neglected tropical diseases (NTDs). The freshwater snails Biomphalaria alexandrina are the intermediate host of Schistosoma mansoni in Egypt. Controlling these snails by medicinal plants is a promising way as it is an eco-friendly strategy. The objective of this study is, to evaluate the molluscicidal activity of ethanolic extracts of three medicinal plants Ziziphus spina christi, Moringa oleifera, Tecoma stans and their effects on the chromosomes and apoptotic changes of B. alexandrina snails in control and exposed snails. Results showed that ethanolic extracts had a molluscicidal activity on B. alexandrina, where LC₅₀ of Z. spina christi, M. oleifera, and T. stans were 108.7, 209.4 and 256 mg/L respectively. The meiotic stages were detected in the normal control group, the first meiotic division begins with long prophase (chromatin network), which is subdivided into four stages; leptotene, zygotene, pachytene, and diplotene. After exposure of each plant extract, there were some alterations in the zygotene stage, which was different in all exposed snails and induced apoptotic changes was observed. Notably, Z. spina christi had a more condensed zygotene stage than the other two plants and significantly increased the percentage of apoptosis than the control group.