This study was conducted to investigate the influence of treatment with fraxetin (7,8-dihydroxy-6-methoxy coumarin), on the lifespan and longevity of Drosophila melanogaster (both sexes), introducing the treatment at different ages and comparing the differences in a situation of stress or not. Different groups were established to determine the maximum longevity (the maximum amount of time that an individual can survive) and the time of life was measured of an homogeneous population until the death of the last individual. This parameter is genetically determined; and is related to the metabolic rate and it appears unchangeable by most environmental factors. From this parameter, the average longevity was determined, establishing an average maximum age between the different subgroups for the same group of treatment, considering the maximum life reached in every subgroup. The third parameter studied is the lifespan (time that 50% of individuals survive), it is affected by both genetic and environmental factors. The object of this investigation was to establish the influence of stress (provoked by an assay of flying capacity) in the lifespan of the flies, and to study how treatment can protect individuals against induced stress. The survival values of the individuals submitted to an assay of flying capacity, during its development until the death of the last individual was evaluated. The three parameters for these individuals were established. Fraxetin administration did not reduce the lifespan in male Drosophila, but prolonged the lifespan and longevity in female flies, especially with a 2-week treatment, both in normal conditions and in a stress situation (the assay of flying capacity was considered as the response to a stress situation). Male Drosophila in a stress situation presented with a reduction of flying capacity, related to age, and also of the maximum life. Whereas, females only presented changes in the flying parameter, without modifications in the lifespan.