High performance liquid chromatographic (HPLC) analysis of methomyl was used in order to measure the residue amount of methomyl as nglg tissue of both terrestrial slug, Lehmenia margr'nata and male white albino rat. Ratios norvegicus var. aibus. The results indicated high performance liquid chromatographic methomyl response after 48 hrs of topical application and poisoned food technique methods at different concentrations against gastrOpod slug, L. marginafa. The distributed amounts of methomyl in different organs of male white albino rate, R. norvegr‘cus var. aibus due to L05 methomyl subcutaneously injection could be summarized as follows: a) Cerebellum tissue contained higher amounts of methomyl than cerebrum by 1.8 folds.