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A two-year field trial was conducted in El-Boustan region, South El-Tahrir Province, El-Behira Governorate, Egypt to decrease mineral nitrogen (N) inputs of sunflower and increase yield and quality of the intercrops to achieve farmer's benefit under sandy soil conditions. A split-plot design with three replicates was used. Quality of sunflower and soybean seeds was tested in the laboratories of Seed Technology Research Department, Field Crops Research Institute, Agricultural Research Center. For soybean crop, average yield of soybean with sunflower was greater by intercropping soybean with sunflower that spaced at 40 cm in the same ridge. Slow-release N fertilizer rates of sunflower did not affect all the studied soybean traits. Also, soybean yield and its attributes were not affected by the interaction between sunflower plant spacing and slow-release N fertilizer rates of sunflower. Seed oil content of soybean was increased by increasing sunflower plant spacing from 20 to 40 cm, meanwhile quality of soybean seeds was not affected by slow-release N fertilizer rates of sunflower or the interaction between sunflower plant spacing and slow-release N fertilizer rates of sunflower. For sunflower crop, intercropping soybean with sunflower that spaced at 20 cm had the highest seed and oil yields per ha compared to the others. All the studied sunflower traits were increased by increasing N fertilizer rates of sunflower from 71.4 to 142.8 kg N/ha except number of leaves per plant. The interaction between sunflower plant spacing and slow-release N fertilizer rates of sunflower affected significantly all the studied sunflower traits except number of leaves per plant. Quality of sunflower seeds was not affected significantly by sunflower plant spacing but it was increased by increasing N fertilizer rates of sunflower from 71.4 to 142.8 kg N/ha. The interaction between sunflower plant spacing and slow-release N fertilizer rates of sunflower did not affect quality of sunflower seeds. Land equivalent ratio values for intercrops were much greater than 1.00 indicating less land requirements of intercropping systems than sole sunflower. Farmer's benefit was achieved by intercropping soybean with sunflower plants that spaced at 20 cm between hills (50% soybean + 100% sunflower) and received 75% of the recommended mineral N fertilizer rate of sunflower under sandy soil conditions.

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