Two field experiment was conducted to evaluate effect of preceding winter crop (Wheat and Egyptian clover), nitrogen levels (90, 120 and 150 kg N/fed.) and foliar minerals application (control, potassium sulphate, and micro-nutrient compound as well as their interaction) were carried out at Exp. Stat., Fac. Agric., Cairo Univ., Egypt during  2015 and 2017 growing seasons. Analysis of data showed that all parameters of Zea mays L. cv. single cross 131 significantly increased grain protein, carbohydrates and oil contents. The highest values of the previous parameters were obtained when maize was preceded by Egyptian clover, while the lowest ones were noticed after wheat. Results indicated that protein, carbohydrates and oil contents of maize grain and grain yields markedly increased with the increase in N rates from 90 to 150 kg /fed. The maximum value of protein, carbohydrates, oil contents as well as, their yields/fed. were recorded with foliar application of micronutrients + potassium. Results also indicated that maize grown after Egyptian clover and Micronutrients + K sulfate foliar application recorded maximum grain protein content (10.1 and 10.6 %), grain carbohydrate content (63.0 and 68.5%) and oil content (10.0 and 9.9 %) in both seasons, respectively, as well as, recorded maximum protein yield/fed. (0.364 and 0.389 ton) and oil yield/fed. (0.359 and 0.360 ton) in both seasons. Maize grown after Egyptian clover and received 120 kg N/fed. combined with nutrients foliar application  of potassium sulphate and micro-nutrients are recommended for high maize grains, protein, carbohydrates and oil yields. On the other hand, maize grown after wheat and received 150 kg N/fed. and nutrients foliar application  of potassium sulphate + micronutrients resulted in producing the maximum maize grain, protein, carbohydrates and oil yields.