The methanolic extract obtained from Cecropia membranacea Trecul (0,5 g/kg v.o.) administered to mice albinos ICR, elicits antiseizure activity (73% of protection) in mice exposed to pentilentetrazol (PTZ, 80 mg/kg, sc.), chemical model of absence crisis. Additionally, the extract conferred significant protection against the maximal electroshock seizure, model of tonic clonic seizures and the parameter of frequency in the elevated plus maze test, screening model of anxiety. On the other hand, the extract lacked effect on the pentobarbitone induced sleep test and in the forced swimming test, screening model for antidepressants. Phytochemical preliminary analysis showed presence of tannin, terpenoid and flavonoid metabolites. This study suggests that C. membranacea could be source of substances with anticonvulsant and anxiolitic properties.