Trials on artificial pollination require knowledge about ponen grains germination, that depends on ponen maturity and also on enviromental factors such as temperature and relative moist. In, this. project those factors were evaluated on the Guanabano (Annona muricata L.) in order to find the best conditions for storing. The best conditions were found at 14.3 (C temperature and 91.6% relative moist, followed by cold room conditioh s at 22 (C temperature and 83.6% relative moist. The worse conditions were at room temperature, that is 28 (C temperature and 86% relativu rnoist. It is boncluded that pollen grains germination' decrease at higher temperatures and at lower relative moist as a result of pollen arains dehydration and loss of viability. The floral aperture stage that showed the highest number of germinated pallen grains was VI, that is O hours of storing, loosing germination power- throught storaging time.