The results of third phase of experiments of seeds magnetic stimulation of Leucaena leucocephala (Lam.) of Wit are presented; work aimed to improving physical methodologies technically feasible, and which can be extrapolated to recovery of wild plant species with potential use. Factorial experiments were performed using levels of magnetic flux density (B) of 30; 62,5; 125; 200 y 250 mT, exposure time between 0,5 y 60 minutes, number of magnetic expositions 1 and 4 times, and time between each of these, 24 hours and 7 days. Proving that in some doses the magnetic field generates a positive influence on Leucana plant development, affecting mainly root length, leaf mass and nitrogen percentage. Results show that B has a greater influence than exposure time in seed pretreatment for this species. The better responses were given to 30 mT, and it is detected that the action of magnetic stimulation on this specie presents an accumulative behavior.