This research was conducted to determine the effects of twenty four different fertilizer combinations included four different nitrogen doses (0, 75, 150 and 225 kg N ha(-1)), two phosphorus doses (0 and 50 kg P2O5 ha(-1)) and three potassium doses (0, 50 and 100 kg K2O ha(-1)) on root yield and yield components of fodder beet (Beta vulgaris var. crassa Mansf.) under Isparta conditions in the 2007 and 2008 growing seasons. It was determined that the effect of fertilization were significant all parameters except root dry matter content. Fertilizer applications increased root yield, dry matter yield, crude protein content, crude protein yield, root diameter and root length but decreased ADF and NDF contents of roots. The highest root yield and crude protein yields were obtained from 225 kg ha(-1) N + 50 kg ha(-1) P treatments.