The investigation was developed during the period of 2008-2009 aiming to determine the technical effectiveness of an extract of Furcraea hexapetala (Jacq.) Urban (maquey) on the insect Myzus persicae Sulzer, in laboratory and under field conditions. Laboratory assays were carried out to determine the technical effectiveness of natural extracts of F. hexapetala on M. persicae, spraying insects reared on potato and pepper leaves in Petri dish and  in the field conditions the  sprays were done with  the extract on natural insect populations in potato and pepper crops. In all the cases five treatments were studied: the extract of the plant to 12.5%, 25%, 50% and 100% obtained starting from the juice of the leaves, and a control. Moreover an assay was carried out to determine the technical effectiveness of different fractions of the extract of F. hexapetala, obtained with different solvents, on that aphid specie. The extract of F. hexapetala manifested technical effectiveness on the insect higher than 73% "in vitro" and 71% under field conditions as much in pepper as in potato. At the 48 hours the fraction of the extract of F. hexapetala in n butanol reached 100% of effectiveness. This confirmed that the insecticide effect of the plant is due to the present saponins in the ethanol-water extract and concentrated through successive processes in the n butanol solvent.