The actual yields of sugar beets harvested by farmers in Poland are much below the yielding potential of currently cultivated varieties, even when grown on fertile soils. Deficiency of micronutrients can be considered as a factor which prohibits reaching a state of nutrient balance, especially in nitrogen, by a crop. The aim of the study was to assess the effect of foliar application of multi-microelement fertilizers on a sugar beet nutritional status in early stages of canopy growth and, in turn, on yields of taproots and recoverable sugar. For this purpose, in two growing seasons, 2005 and 2006, eight field trials were setup in the region of Wielkopolska on fertile soils originated from sandy loam. A simple experimental design comprised three treatments: (1) control (a plot fertilized only with NPK), and (2) multi-microelement fertilizer composed of cations (Mi), (3) cations plus boron (MiB). It has been found that the applied micronutrient fertilizers had a significant effect, irrespectively of the field location and seasonal yield variability, on the sugar beet nutritional status, especially in terms of nitrogen. Yields of taproots have increased by 31.6% and 22.1%for the NPK+Mi and NPK+MiB treatments, respectively. Almost the same degree of increasewas noted for yields of recoverable sugar. The achieved nitrogen balance at the stageof harvestable part development, as measured at BBCH-43, was probably the main reasonfor high positive response of sugar beet crop to external supply of micronutrients. All the analyzed standards of sugar beet nutritional status, DRIS indices, responded to the investigated experimental factor, i.e., foliar application of multi-microelement fertilizer, but only those for nitrogen underwent a change from negative to positive values, thus enabling us to make a reliable yield prognosis.