Abstarct: In order to investigate the effect of phosphate solulolizing bacteria, humic acid and phosphorus fertilizer on corn, a test was carried out in a research field of Semnan Agricultural Research Center (Shahrood) in Shahrood, in 2016-2017. The experiment was conducted as factorial in randomized complete block design with 3 replications. The first factor was used in 4 levels of soil phosphate solulolizing bacterial isolates, baxsed on the recommendations of the Soil and Water Research Institute and under the names B0, B1, B2, B3.The second factor was the two levels of application of fertilizer, triple superphosphate (including P0: without phosphate fertilizer, P1: 100% recommendation baxsed on soil test) and third factor in two levels of humic acid consumption including C0: without use Humic acid and C1: consuming 100% of the recommended amount of humic acid.The results of this experiment showed that stem diameter, leaf area and biological yield of corn fodder increased with phosphate solulolizing bacteria.Triple superphosphate fertilization also improved biological yield. Plants that received humic acid showed higher leaf area and biological yield. In this research, the interactions of phosphorous fertilizer and B3 bacteria showed higher elevation, and the triple interaction effects of the factors tested showed the highest fresh weight.The effect of qualitative traits showed that only phosphorus levels increased under the influence of phosphate solubilizing bacteria.