Using of nitrogen fertilizers may increase the photosynthesis and yield of crop plants. Hence, we investigated the effect of chemical nitrogen and rhizobium fertilizers on the photosynthesis and yield components of red beans (Sayad cultivar) in an experiment as a randomized complete block design with 4 replications in Al-Mahdi town, Azna, Iran. The treatments included zero (control), 100 and 200 kg ha-1 of urea and rhizobium, and rhizobium + 30 and 50 kg ha-1 of urea. The results of this experiment showed that the effect of fertilizer treatments was significant on leaf area index, level, efficiency and contribution of current photosynthesis, level, efficiency and contribution of remobilization, dry weight in pre-flowering and maturing stages and grain yield and its components. The chemical fertilizer and rhizobium application increased the amount of all the above traits except for the contribution of current photosynthesis. There was a strong correlation between grain yield and the level, efficiency and contribution of current photosynthesis and the level, efficiency and contribution of current of remobilization. The examined wide range of nitrogen fertilizers were potent to increase the photoassimilates production and, hence, yield and yield components of red bean in this region.