The aim of this research is to develop and evaluate a topper unit for sugarbeet suitable for Egyptian conditions. Field experiments were carried out at El-Serw Agric. Res. Station, Damietta Governorate during 2013/2014 season. The performance of the developed topper unit was evaluated at different speed ratios of 0.007, 0.0076, 0.0080 and 0.0085 under knives positions; faced (F) and edged (E) and flails number solo (S) and doubled (D). Different flail lengths of 15, 20, 25 and 30 cm were tested. Over topping, under topping beets, un-topped beets, damaged beets, topping efficiency, actual field capacity, field efficiency, energy requirement and total costs were estimated. Due to increasing speed ratio increased actual field capacity and field eff. Both doubled and faced flails showed the best results under all treatments. Generally, the results recommended that topper unit should be used at speed ratio of 0.0085 with doubled-faced-flail (DFF) that recorded highest value of topping eff. (97.30%). On the other hand, the lowest value for over topping beet (2.4%), undertopping beets (2.8%), un-topped beets (2.2%) and damaged beets (2.77% ) were recorded. Hence, the best value of actual field capacity (0.92 fed/h) and field eff.(83.4%) were recorded at speed ratio of (0.0085). Energy requirement decreased by 13.22 % while total costs decreased by 78.27% comparing to manual topping costs. Flail length of 25 cm showed the desirable results with all treatments. Doubling and facing flails position had a high significant effect on all treatments.