During the past few decades the constant growth of the production of high quality wines has been noted in the Zadar County, although, apart from few exceptions, those wines are not recognized as such in the local Croatian market. However, they do have a great significance for local tourist offers. Ochratoxin A (OTA), mycotoxin which is produced by some varieties of species Aspergillus and Penicillium, can be found also as a wine polluter, especially in red wines. Due to nephrotoxicity, imunosupression and suspicion of carcinogenic effects of OTA, its concentration in food and raw materials has been limited by EU regulation. According to climatological and ecological conditions, Zadar County is situated on the border between the areas of high and low risk of wine contamination with OTA. For the purpose of this study the samples of grape berries were taken from four vineyards in Zadar County. Those vineyards differed in position as well as in climatological, pedological and ecological characteristics and also in cultivation styles. The results showed the existence of fungi which cause the appearance of OTA in Zadar County, however, their concentration was extremely low. The greater amount of toxigenic fungi was isolated in the vineyards where ecological production was applied, however, also in that case their concentration was low. The comparison of samples from June and September showed that greater amount of ochratoxigenic fungi was isolated from grape berries in September. From these results it can be concluded that a certain risk of contamination exists, however it is very low. Regardless, it is necessary to raise the awareness of wine producers in relation to this problem as well as to plan the measures of prevention and control of OTA in red wines of Zadar County.