To examine the effects of soil nitrogen addition rates, yeast addition timing, and foliar yeast spraying on the quantity and quality traits of sugar beet throughout 2020–2021 and 2021–2022 seasons, two trials were undertaken at a field in Wazeer Village, Belqas District, Dakahlia Governorate, Egypt. Four duplicates of each field experiment were used in the strip-split plot design. The greatest values of root length and diameter, plant fresh weights of roots and foliage, and roots and top yields/fad were reached when fertilizing by 115 kg N/fad. The greatest values of total soluble solids, sucrose and apparent juice purity, extractable white sugar percentages, and sugar yield/fad were obtained with 69 kg nitrogen fad^-1 fertilization. By fertilizing with 92 kg N/fad, gross white sugar yield/fad reached their peak. The highest root and leaf fresh weights per plant, root length and diameter, extractable white sugar %, and root, top, and gross sugar yield/fad were produced by foliar spraying at 100-days after seeding or adding yeast to soil. Highest values of total soluble solids, sucrose, apparent purity and extractable white sugar percentages and white sugar yield/fad were obtained with using yeast as soil addition and foliar spraying at 50 days after sowing in the two seasons. It is possible to suggest fertilizing sugar beet plants with 92 kg N/fad to maintain high productivity and quality of sugar beet while also reducing production expenses and environmental damage and sprayed yeast on plants' leaves at 50 days after planting in addition to soil addition.