The objective of this study was to establish whether inoculation of sugarbeet with Azotobacter chroococcum affects, in field conditions, the yield of roots, sugar content and the yield of crystal sugar. We used six strains of Azotobacter chroococcum (2, 3, 5, 8, 14 and 2/1) which originated from the Collection NSCNFB and which had been isolated from sugarbeet rhizosphere. The choice of the strains was made on the basis of previous investigations of their effectiveness in association with sugarbeet hybrids. On average, all strains under study brought increases in root yield, with the exception of strains 2 and 3 in 1997. The highest positive effect on root yield was obtained with strain 2/1 in 1996 and with strain 5 in 1997. In 1996, Azotobacter chroococcum strain 5 increased the yield of roots of the variety Dana by 16.4 t/ha. In 1997, strain 5 increased the yield of roots of Hy-11 by 9.23 t/ha (Table 1). On average, all Azotobacter chroococcum strain increased the content of sugar. Strain 8 had the highest effects in both years of study. In 1996, Azotobacter chroococcum strain 2 increased the content of sugar in Hy-11 by 1.15% in relation to the uninoculated control variant. In 1997, Azotobacter chroococcum strain 8 increased the sugar contents in Hy-11, Delta and Dana by 0.82, 0.69, and 0.92%, respectively (Table 2). In 1997, all strains except 2, 3 and 2/1 increased the yields of crystal sugar of the tested varieties. Strains 8 and 5 were most effective. On average for all three varieties, strain 8 increased the yield of crystal sugar by 910 kg/ha in 1996 and by 780 kg/ha in 1997. In 1996, strain 5 increased the yields of crystal sugar by 2.33 t/ha in the variety Dana, and by 1.39 t/ha in Hy-11 (Table 3). The application of Azotobacter as a bacterial preparation opens new avenues in sugarbeet production, reducing the use of mineral fertilizers and improving the quality of the environment.