The County of Istria, with an area of 2.813 km2, covers about 90 % of the Istrian peninsula. It contains 145.350 ha of agricultural land, which is 51,7 % of the county's area. Most of it, or 56,4 %, is unused or neglected agricultural land, and the remaining part, or 43,6 %, is used for various purposes. Of the total area of agricultural land in certain geomorphological units, 87 % area of White Istria, 60 % of Gray Istria, and 45 % of Red Istria is unused. The aim of this paper is to show the suitability of soil for irrigation on agricultural land of Istria County. Soil characteristics are presented based on a Soil Suitability Map of the Republic of Croatia at a scale of 1:300.000. The suitability of pedosystematic units for irrigation was assessed according to the FAO Land Evaluation Method. A total of 19 pedosystematic units were found in the county, which is shown on the map in 22 soil mapping units. The total area of soils suitable for irrigation in the Istrian County is 78.584,8 ha (68,4 % of the total agricultural area), of which 2.900,7 ha (2,5 %) belong to the S-1 good suitability class, 53.916,1 ha (46.9%) belong to the S-2 moderate suitability class, while 21.768,0 ha (19,0 %) belong to the S-3 limited suitability class. There are 36.362,0 ha of unsuitable soils for cultivation (31.6 % of the total agricultural area), of which 4.906,5 ha (4.3 %) belong to the class U-1 temporarily unsuitable soils, while 31.455.5 ha (27.3 %) belong to the class U-2 permanently unsuitable soils. Considering the area of S-1 and S-2 suitability classes for irrigation, and the fact that 46 % of these soils are located on unused agricultural land, it can be stated that in Istria there are very valuable land resources suitable for planning of intensive and sustainable agricultural development in conditions of irrigation.