In order to evaluate and determine the appropriate nitrogen fertilization the morphological characteristics and seed yield of mungbean three cultivars, an experiment was done as split plot based on randomized complete block design with four replications in summer 2011 in the city of Khorramabad. In this study, different levels of nitrogen fertilizer (control, 50, 100, 150 kg/ha urea) as sub-plots and three mungbean cultivars (Partow, Gohar, locally) was considered as the main factor. The result of analysis variance on morphological characteristics on seed yield showed that between different cultivar in the eyes of first pod height and seed yield were significant at 5% level probability. In addition, between different amounts of nitrogen fertilizer for stem diameter and number of node and seed yield showed significantly different. Interaction between urea fertilizer and cultivars, number of nodes and seed yield were significant effect at 1% and 5% level probability. The highest seed yield of 8.9 grams per square meter and the number of sub-branches with (1.5) and the height of the first pod from ground level with (25.51 cm) and stem diameter (1.13 cm) and number of nodes (8.28 pcs) and pod length (7.5 cm) was obtained at 150 kg/ha urea. Between different amount of nitrogen fertilizer, 150 kg/ha urea, showed higher values than the other. In this experiment, 150 kg/ha nitrogen fertilizer with partow cultivar (V1) is the most appropriate treatment and suitable for this region.
