The olive (Olea europaea L.) is one of the most important fruit species in the Adriatic part of Croatia. The orchard productivity highly depends upon the combination of planted cultivars. Simultaneous flowering periods enable cross-pollination, fertilization and fruit set of different cultivars if compatibility between recipient and polleniser trees exists. A number of economically valuable olive cultivars have been introduced in Croatia during the last twenty years. Italian cultivar ‘Leccino’ is one of the most represented cultivars in newly planted orchards. Introduction of cultivars was not followed with experiments of their compatibility with autochthonous Dalmatian cultivars. The aim of the research was to determine the duration of flowering periods, self-compatibility, and cross-compatibility within and between autochthonous cultivars ‘Drobnica’, ‘Lastovka’, ‘Levantinka’, ‘Oblica’, and introduced cultivar ‘Leccino’ under conditions of Middle Dalmatia. The experiment was conducted in a twenty-year-old olive orchard during two flowering seasons. Simultaneous flowering and the full bloom were noticed for ‘Leccino’, ‘Drobnica’ and ‘Oblica’. Self-incompatibility was not found for tested cultivars. Cross-pollination was more efficient than self-pollination in induction of fruit-set in almost all cultivars. According to the higher fruit sets following cross-pollination of Croatian cultivars and Italian cultivar ‘Leccino’, compared to self-pollination, increase in tree productivity is expected in the presence of selected cultivars in the newly planted orchards.