Abstract: The effects of hydroalcoholic extract from the leaves of Gochnatia polymorpha sp. floccosa on the contractile responses of the isolated guinea-pig ileum were investigated using a force displacement transducer amplifier connected to a physiograph. Isolated ileum preparations were set up for recording of isometric contractions in 5 mL jacketed organ baths containing oxygenated Krebs-Henseleit solution at 37°C under 1 g of load. G. polymorpha floccosa extract inhibited the contractile responses in a dose-dependent manner against different agonists. The profile of inhibition was noncompetitive to acetylcholine, histamine, serotonin and bradykinin-induced contractions. IC50s (and maximal inhibitions) values obtained were 247 μg mL-1 (83.1%), 818 μg mL-1 (72.62%), 450 μg mL-1 (75.82%) and 210.09 μg mL-1 (97.35%), respectively. These findings support the popular use in folk medicine of this plant as an antispasmodic on smooth muscles contractions.