Anxiolytic effects induced by benzalphthalides on mice have been evaluated. The evaluation was based on the spent time and the number of entries of animals into the open arms in the elevated plus maze test. Single administration of benzalphthalides 1 and 11 induced significant increments in both parameters, thus revealing their potentiality as new leads for the development of non-benzodiazepinic and non-nitrogenated antianxiety agents.