Sour cherry is one of the most important stone fruits of Rosaceae family. Iran ranked 3th to 6th among the main sour cherry producer countries in the world. Most of the sour cherry cultivars are self-compatible but self-incompatible cases have been reported currently. Allotetraploidy of sour cherry complicates the self-incompatibly segregation in the progeny and because of this trait less studies have been accomplished specially in Iran. In the present study, pollen-pistil compatibility relationships among some sour cherry cultivars and selected genotypes were investigated by controlled pollination and pollen tube penetration by fluorescence microscopy. Three self-incompatible cultivars (S.I. 209, S.I.301 and E.J.175 as the pollinated parents) and genotypes (K110, T145, T140, K202, M171 and M150 as the pollinizers) were selected. After controlled pollination fruit set was studied and the pollen tubes growth along the style was studied using fluorescent microscope. Results showed that cross-incompatibility was not observed among the studied cultivars and genotypes. Therefore, they could be used in the breeding programs and orchards establishment based on their synchronized blooming time.