The aim of this research study was to evaluate the effect of essential oil from the dried leaves of Melissa officinalis L. on isolated ileum Cavia porcellus. 6 specimens Cavia porcellus, adult males, of whom ileal samples, which were mounted on isolated organ bath, using the extracted PowerLab used. distilled water, essential oil 0.5%, 1%, 2.5% and 5% and N-butyl bromide hyoscine 20 mg / mL: treatments were applied. Prior to each treatment spasmogen acetylcholine was added and contraction recorded as the respective treatment was added. The volume applied to each treatment was 0.2 mL respectively. It was evaluated based on the amplitude and frequency of contraction registered. The results showed that the essential oil of Melissa officinalis L., reduced contraction amplitude similar to the pattern, N-butyl bromide hyoscine (p = 0.000). No data were obtained satisfactory with respect to the...