Antibacterial lysozyme-like activity against Micrococcus luteus in eggs and some tissues of snails Helix aspers maxima and Achatina achatina was detected in a turbidimetric standard assay. The bacteriolytic activity in Helix aspersa maxima was higher than in Achatina achatina. After the application of the bioautography technique, several lytic zones of Micrococcus luteus were observed in both studied species. Electrophoresis in denaturing conditions followed by immunodetection of lysozyme using EWL antibodies indicated the presence of several lysozyme forms in the tested snails.