Picual olive flowers were examined under fluorescence microscope after being exposed to different pollination treatments. Cross, self and open pollination were examined. Also, the effect of pollination stage of Picual flowers was studied. Investigation of  Picual flowers by means of fluorescence microscope showed that percentages of Kronaki and Coratina pollen germination on the surface of Picual stigmas, percentage of penetrated styles and number of pollen tubes at the end of the stylar canal were higher when pollination was carried till three days after anthesis compared to delayed pollination and ovules viability started to decline from the 4^th day after anthesis. Cross pollination by Kronaki pollinizer showed the highest significant percentages of pollen germination on the stigma, pollen tube growth through the styles and number of pollen tubes at the end of the penetrated style compared to other pollen donors. Thus, it can be recommended to use Kronaki as a pollinizer for Picual to ensure efficient pollination and fertilization.