Two field experiments were carried out in the Experimental and Research unit, Faculty of Agriculture, Mansoura University in the two winter seasons of 2015 and 2016 to study the impact of foliar application by ascorbic acid (i.e. without, 150 and 300 ppm) under four nitrogen fertilization sources (ammonium nitrate, ammonium sulphate, calcium nitrate and urea) on growth and yield of spinach plants (cv. Dash). The results indicated that vegetative growth attributes (Plant height, plant fresh weight, leaves fresh weight, leaves number and leaves area) per plant, leaves chemical composition (N, P, K, chlorophyll a, chlorophyll b and carotenoids), yield and its chemical quality (blades and petioles fresh weight, dry matter % and NO₃ content), Vit. C, TSS, fertilizer use efficiency, hill weight and yield per fed.) were affected significantly by nitrogen form. Urea recorded the highest values of the previous parameters except NO₃ content to blades and petioles. As for the effect ascorbic acid, the data show that the mentioned attributes were increased compared to the control. The interaction between nitrogen form and ascorbic acid showed that urea form combined with 300 ppm ascorbic acid recorded the highest values for most effective previous characters and the lowest values for NO₃ content to blades and petioles.