To investigate the effect of Zn spraying and plant density on thousand seed weight(TSW), biological yield, seed yield, harvest index(HI) , straw yield and seed protein yield in green gram crop, an experiment was conducted in summer 2010 in Koohdasht. Experiment was performed in Split plot randomized complete block design with three replicates. Fertilizer application on three levels of control (spraying water), applied in a rapid growth phase and two times spraying with two in thousand concentration of Zn fertilizer was considered. The results show the superiority of TSW, seed yield, HI and seed protein present in spraying method. Analysis of variance showed that the effect of plant density on seed yield, biological yield, HI and protein content was significant and the highest yield of 1787.5 kg /ha was obtained to density of 33 plants per square meter and once spraying that this treatment is justified for the region.