Laboratory and field experiments have been conducted to evaluate the molluscicidal activity of certain pesticides compared with Gastrotox 5
% ( Metaldehyede),  ( the recommended compound) against Monacha obstructa land snails under laboratory and field conditions at Plant Protection Research Institute Mansoura Branch, Dakahlia Governorate during 2012 season.    Results can be concluded that the molluscicidal activity of tested compounds under laboratory conditions were arranged in the descending order according to their activity of LC₅₀ values as follows: Neomyl < Mesarol < Kafrothrien < Agriflex < Koragien<  Agrinet < Nafigator  Monacha sp. in field after 3 days (I.K) were (65.98, 63.44, 70.22 , 71.28 and 71.27 % ) Also, reduction percentages ( residue ) after 28 days were ( 91.39, 78.66, 94.65, 91.55 and 91.48 %) reduction for Agrinet, Kafrothrien, Gastrotox, Neomyl and Meserol, respectively.