The vascular flora of Significant Landscape Gornji Kamenjak in Istria was investigated in different vegetation periods from 2012 to 2013, and a total of 507 plant taxa (468 species and 39 subspecies) were recorded. Part of them werw previously registered, while some are recorded for the first time. The studied area was poorly investigated in the past, therefore there was a need for this study, representing a very detailed floristic survey of the area. The most dominant families were grasses (Poaceae, 11.8%), legumes (Fabaceae, 10.6%), daisies (Asteraceae, 6.5%) and mints (Lamiaceae, 5.5%). The domination of therophytes (37.0%) indicates that the climate of Gornji Kamenjak shows a high influence of the Mediterranean climate, followed by hemicryptophytes (30.8%) and geophytes (12.6%). We recorded a total of 11 invasive species across the whole investigated area, as well as the occurrence of 15 endangered and 13 endemic plant taxa. The results of our research of autochthonous vascular flora indicate high richness and diversity of plant species in the studied area.