Nitrogen is essential for all vital plant processes and plays an important role in the growth, yield and quality of crops. In this study, the effect of 100, 150, 200, 250 and 300 kg of pure nitrogen per ha in the form of urea fertilizer (46% nitrogen) and ammonium sulfate (21% nitrogen) on leaf number and length, yield and garlic components were investigated. To perform the field experiment, the split plots were tested in a randomized complete block design with four replications. The type of fertilizer was in the main plot and the level of fertilizer was in the sub-plots. Garlics of Hamedani mass were planted on October 20, 2007 in plots with dimensions of 2*4.1 m². The results of this study showed that the effect of fertilizer type on single plant garlic weight, garlic length and diameter, average number of garlic, length and diameter of garlic and single garlic weight was not significant and on leaf length and number and yield were not significant. With increasing the amount of fertilizer to the level of 200 kg of pure nitrogen per hectare, the amount of yield and other traits increased slightly and then decreased with increasing the amount of fertilizer to the level of 300 kg / ha. The highest yield was observed in single plant garlic weight, length and diameter of garlic, length and diameter of garlic and number of garlic in 300 kg of pure nitrogen per hectare. The highest number and length of leaves were observed in the treatment of 300 kg of pure nitrogen per hectare and the lowest in the treatment of 100 kg of pure nitrogen per hectare. Yield also showed a positive and significant correlation (p £ 0.01) with leaf number and length, garlic length and diameter, garlic length and diameter and single-garlic weight.