Studies of various plant species have shown that a significant portion of the genes that are expressed in the sporophyte are also expressed in the microgametophyte (pollen grain). Consequently, selection pressure applied to pollen may aid in the modification of qualitative or quantitative characters of the derived progeny. To verify this hypothesis in common bean (Phaseolus vulgaris), a study of the effect of high temperature stress on pollen grain in three cultivars in F 1 and F 2 generations was conducted by means of in germination techniques and controlled pollinization with stressed pollen. In vitro germination was inversely related with the level and duration of high temperature stress. As 50°C the stressed pollen showed considerable decrease in germination. Evaluation of germination of pollen between progenies showed no increase in tolerance to high temperature of microgametophytes. Greater progress in selection of microgametophytes be obtained using larger quantities of pollens, which would provide greater opportunity to select for vigor. The origen of the variability in the germination of pollen in cultivars in the flowering period should also be examined.