The possibility of using the naturally occurring rotifers, present inadvertently in the snail aquaria, as biological control agent against snait eggs was tested. Two species of rotifers namely Rotaria rotatoria and Philodina acuiicornis were identified, isolated and cultured intensively in controlled clean aquarium. Rotifers were fed on green algae of the genus Scenedesmus* Experiments were designed to test the ability of rotifers to destroy the snail egg masses coinciding with the abundance of rotifers in the media. The damage occurred to the snail egg masses by adult rotifers was monitored and assessed. The different stages leading to the egg masses destruction were identified. The results showed that the stage of development of embryos and the availability of rotifer's food were the two factors controlling this process.