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Total 480 soil profiles covering an area of 31227 ha were analyzed for need of hydromelioration project in area of eastern part of Sava valley in Croatia. It is narrow belt longitude approximately 150 km and width form 5 to 10 km in west-eastern direction. Slobostina and Josava rivers are border toward west and east direction, respectively. Also, it is delimited by river Sava toward south and by Psunj, Pozeska gora and Dilj Mountains toward north. Aim of this study was testing available phosphorus (P) and potassium (K) status (Ammonium-Lactate-method) in surface (0-30 cm) soil layer of these soil profiles. P availability in about 30% of the tested agricultural land (9440 ha) is very low P (until 5 mg P2O5 100 g-1 of soil), next 32% (9897 ha) are in the range low P availability (from 5.1 to 10 mg), while only 17% (5445 ha) has good or very good P availability (above 20 mg). Especially a high frequency of low P availability was found in vertic gley, amphygley and hypogley soils (total 8680 ha or 28% tested agricultural land). Concerning the degree of K availability nearly one third of the tested area (9989 ha or 32%) is low supplied with K (less than 10 mg K2O/100 g of soil). Especially high frequency of this range of K availability is found in hypogley (4629 ha or near 50% of area covered by this soil type). The most favorable K status was found in semigley alluvial soils: only 7.7% of the area of this soil is moderate supplied with K and even 27.5% of the area is in range of very high K availability (above 25 mg K2O/100 g of soil). We recommend different amounts of ameliorative P and K fertilization every fifth year and ordinary fertilization every year. For example, the application of 1000 kg and 500 P2O5 either or K2O/ha for soil containing very low (less than 5 mg /100 g) and low nutrient levels (from 5.1 to 10.0 mg/100 g), respectively. For the remaining area we suggest P and K fertilization according these nutrients removal.