The present work was carried out to calculate the half lethal concentrations (LC50) of three inorganic fertilizers (balanced, high phosphorus and high nitrogen fertilizers) on Biomphalaria alexandrina snails and to demonstrate measurable effects on infected B. alexandrina with Schistosoma mansoni miracidia that were exposed for one week to 1/4 LC50 (126.4, 400 and 2375 ppm) separately of (balanced, high phosphorus and high nitrogen) fertilizers, respectively. The obtained results showed that the survival of all treated infected snail groups at the 1st shedding were significantly less than the control group. Moreover, results revealed a marked reduction in the infectivity of the infected snails especially those exposed to sublethal concentration of high nitrogen fertilizer when compared to control. In addition, the cercarial production of all treated groups was completely suppressed. These infected snails exhibited histopathological alterations, which is associated with severe damage in the digestive gland cells as well as the mother sporocysts of treated infected snails. Our study revealed the biological and histopathological effects of three inorganic fertilizers on infected Biomphalaria alexandrina snails.