The relationship between pollination and pollen germination was studied in six cultivars of apple tree ('Golden' and 'Royal Gala'), pear ('Conferencia' and 'Blanquilla'), peach ('Amarillo Agosto') and nectarine ('Fairlane'). The observations were determined by fluorescence microscopy. In all cultivars, when the ambiental conditions were favorables. In these conditions pollination and pollen germination were good and pollen germination was influenced by the amount of pollen on the stigma.