Abstract: In order to clarify the application effect of compound bacterial agent on soybean in saline alkali land, taking the pot experiment soybean variety Jiyu 86 as the material, the effects of compound bacterial agent inoculation on soybean phenotypic characters, physiological characteristics and yield were studied to provide theoretical basis for the application of compound bacterial agent on soybean in saline alkali land. The results showed that the application of compound bacterial agent reduced the seedling emergence rate and seedling emergence potential by 2.22% and 6.67%, respectively. The plant height and stem diameter of BF treatment were higher than CK, while the stem diameter was lower than CK. The leaf area of BF was 3.85%, 5.78% and 3.93% higher than that of CK at node stage, pod beginning stage and seed filling stage, respectively. Compared with CK, chlorophyll SPAD value of BF decreased firstly and then increased at the beginning of pod stage and seed filling stage. There were no significant changes in pod, SOD activity and MDA content in different treatments. The total density, total coverage and total aboveground biomass of weeds in BF were 467.0 plant·m^-2, 11.94% and 90.95 g lower than those in CK, respectively. The stem dry weight per plant, effective pod number per plant, seed number per plant and 100-seed weight of BF were 1.97 g, 4.0, 10.22 and 3.12 g higher than CK respectively. There was no significant difference between treatments（P＞0.05）, but the yield per plant of BF treatment was 10.71 g, which was significantly higher than that of the control（P＜0.05）. Therefore, the addition of compound bacteria can promote the growth of soybean plants and inhibit the growth of weeds, so soybean yield was increased in the treatments.