Effect of acetylsalicylic acid, methomyl compound, abamectin bioinsecticide and the joint action of methomyl or abamectin with acetylsalicylic acid were determined on some biochemical parameters (alkaline, acid phosphatase, total protein, lipid and cholesterol) against two land snail species, Eobania vermiculata and Monacha obstructa under laboratory conditions. Snails were tested with LC50 of each tested compound and their mixture using contact technique. Results showed that the combination of acetylsalicylic acid and methomyl exhibited the highest effect on all biochemical parameters. The LC50 of acetylsalicylic acid caused desiccation and adhesive for snail body of both species. The histopathological effect of LC50 of acetylsalicylic acid on the tissues of mucus gland was studied in both snail species. It was partial as well as complete disappearance, necrosis and atrophy of mucus glandular tissue of E. vermiculata. While it caused focal necrosis especially underneath necroses destructed covering epithelium in association with degeneration in case of M. obstructa. Under field conditions, the high efficiency concentrations of tested compounds were tested as a spray. Results revealed that the combination of methomyl and acetylsalicylic acid enhanced the molluscicidal activity against both land snail species in harmony with the result under laboratory condition.