Two field experiments were carried out during 2007/2008 and 2008/2009 seasons at Kafr El-Hammam Research Station, Sharkia Governorate to study the effect of planting densities and potassium fertilizer levels as well as their interaction on sugar beet productivity. Increasing plant densities from 28000 to 42000 significantly increased root length, diameter, fresh weight/plants, sucrose%, total soluble solids (TSS%), phosphorus % in roots as well as top, root and sugar yields (ton/fed) in both seasons. Plant density at 42000 plants/fed was the best treatment, where it gave the highest values on most traits under study. Potassium fertilizer level at 36 Kg K₂O/fed gave significant increase root length, diameter, fresh weight/plant, total soluble solids% and root yield in both seasons as well as sugar yield in the 1^st season only. In general, potassium at the level 36 kg K₂O/fed was more effective than at 18 kg K₂O/fed. Interaction between plant densities and potassium fertilization levels do not gave any significant increase on all studied traits. In general it can be concluded that sowing sugar beet with 42000 plants/fed and potassium fertilizer levels at 36 kg K₂O/fed were the best treatment for maximizing sugar beet productivity in the newly reclaimed sandy soils under the environmental conditions of the present study.