An experiment was conducted to evaluate effect of urea fertilizer on yield and yield components of Zea mays L. Using Randomized Complete Block Design (RCBD) split plots in three replications in agricultural research farm of Balkh University by 2019. Doses of urea used in this experiment were 0, 80, 160 and 240 kg ha-1 , respectively. It has been found that amount of nitrogen fertilizer (urea) had significant effect on yield of maize at p<0.05. The higher level of nitrogen caused the higher grain yield, number of kernels per ear, the number of grains per ear row, ear diameter, cob length, grain per plant and plant height. As a result 7.76 ton ha-1 was recorded as high yield while 240 kg ha-1 urea was used, and 5.12 ton ha-1 was recorded as low yield in treatment one with 0 kg ha-1 of nitrogen fertilizer. Finally, as a result using 240 kg ha-1 nitrogen fertilizer is recommended.