Many trials have shown that high yields and quality can only be obtained with a minimum plant population of 80,000 plants/ha. If the plant population greatly exceeds this value, farmers are concerned about an increase of harvesting losses. The aim of the present research was to examine the effect of plant density and lifting speed on harvest losses. The field trials were established in 1998 and 1999 with 4 levels of plant density and 2 levels of lifting speed. A split-plot design with 3 replicates was used. The treatments were harvested with a 6-row self propelled tanker harvester. The setting was optimised for each plant density and each speed. The performance of the tanker harvester was assessed for loss of whole beets and of broken tips. The overwhelming proportion of the losses in both trial years arose from tip breakage. The results indicate that plant density does not substantially affect the amount of losses, while high lifting speed tends to increase the amount of losses.