In order to study the role of foliar spraying with biostimulants substances and fertilizing with nitrogen mineral fertilizer on productivity and quality of sugar beet, a field experiment was performed during 2015/2016 and 2016/2017 winter seasons at Tag Al-Ezz, Agricultural Research Station Farm, Dakahlia Governorate, Egypt. Strip-plot designs with four replicates were used. Spraying plants with 150 ml yeast extract/liter plus 1.5 ml humic acid/liter as mixture recorded the highest means of all studied characters. However, spraying with 150 ml yeast extract/liter came in the second rank, followed by spraying with 1.5 ml humic acid/liter, then spraying with water and lastly without (control treatment) in the two seasons. Decreasing mineral nitrogen fertilization from 100 to 85, 70 and 55% from the recommended dose (90 kg N/fed) caused gradual reduction in all studied characters, with exception sucrose and apparent purity in both seasons. Highest values of root, top and sugar yields per fed were recorded with adding 100 or 85 % from the recommended dose without significant differences between them during growing seasons. For maximizing sugar beet productivity and quality and decreasing environmental pollution and cost could be succeeded with spraying plants twice with the mixture of 150 ml yeast extract/liter plus 1.5 ml humic acid/liter and fertilizing with 76.5 kg N per fed as soil application under environmental conditions of Dakahlia Governorate, Egypt.