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Two field experiments preceded by an incubation lab experiment were carried out to study the effect of a composite soil amendment prepared by the physical mixing of bentonite, feldspar, and/or zeolite with the compost and/or the gelatin and carboxy methyl cellulose (CMC) on sandy soil. Treatments in triplicates were distributed in a split-plot experimental design including a control treatment (without application). The main factor (I) was two irrigation levels: I-1 = 70% and I-2 = 100% of the wheat water consumptive use (CU m3 ha-1). The sub-factor (A) was the composite soil amendments applied at a rate of 3.5 Mg ha-1 in 11 treatments. The wheat (Triticum activism L.) was cultivated during the two successive winter seasons of 2021 and 2022. The lab results have indicated that the composite feldspar/compost/gelatin/CMC has increased the soil aggregation and moisture content after one day and 100 days of incubation. The mixed composite compost/gelatin/CMC has resulted in a significant variation in the aggregate fractions >1.0, 1.0-0.25, and <0.25 mm. The fine aggregates (<0.25 mm) were decreased compared to the CL up to the 1st 45 days. The moisture content for the CL, compost/gelatin/CMC mixed with the bentonite, feldspar and zeolite after 100 days were 18.1, 28, 29.4 and 25.5%, respectively. The field results showed that the most significant relative increase in the mean values of the available N, P, and K were for the feldspar/compost/gelatin/CMC composite by 90.7, 65.6, and 32.6%, %, respectively. For the wheat grains yield (Mg ha-1), the most significant increase in the mean values relative to the CL was by 62.1% obtained by the feldspar/compost/gelatin/CMC composite. The bentonite/compost/gelatin/CMC and the zeolite/compost/gelatin/CMC composites have increased the yield mean value by 45.3% relative to the CL. The studied soil amendments can be recommended as effective tools for increasing the water retention and soil aggregation so that improving water conservation in sandy soil.