Peanut and soybean are important oilseeds and cash crops in China, however they are also vulnerable to aflatoxin contamination, which seriously threatens food safety and restricts industrial development. The prevention and control of aflatoxin occurrence in food is currently an intense research challenge globally. We first put forward the research idea of coupling the aflatoxin green control with the promotion of root nodule nitrogen fixation, based on the research idea, the microbial agent ARC-BBBE was invented. In this study, the effect of on-the-field application of microbial agent ARC-BBBE in the control of Aspergillus flavus and its toxin on peanut was reported. The research was carried out by investigating the effects of ARC-BBBE on biological and economic traits of peanut, and identifying the effects of ARC-BBBE on nodulation and nitrogen fixation of peanut and soybean, to provide theoretical basis and scientific guidance for controlling aflatoxin contamination and reducing the fertilizer and pesticide use from the source in the field. In field control trials, ARC-BBBE was applied to the soil at a dosage of 30 kg/hm2 with base fertilizer during planting in the peanut-producing provinces of China for 2 consecutive years. At the same time, peanut and soybean pot experiments were also conducted. The level of aflatoxin in the soil was investigated by the spread plate method. And the aflatoxin content in peanut samples was determined using high performance liquid chromatography （HPLC）. Measurement of the nitrogen fixation activity of root nodules was performed using acetylene reduction assay. Finally, the number and weight of root nodules were calculated using a 5-point sampling survey. Results showed that ARC-BBBE significantly reduced the abundance of aflatoxin-producing fungi in soil and the level of aflatoxin in peanut, with an average reduction of 66.5% in the abundance of toxin-producing fungi and decrease of 83.5% in aflatoxin content. The application of ARC-BBBE resulted in a general super nodulation phenomenon in peanut roots, and its nitrogenase activity was also verified in this work. The average number of nodules increased more than 10 folds （50 folds in poor soil areas）, the nodule weight increased more than 8.8 folds, and the nodule nitrogenase activity per gram increased more than 5 folds. The fruit filling rate and yield were significantly increased and the leaf color was dense green. In addition, the results of peanut pot experiment in greenhouse showed that the number of nodules was 2.2 folds higher, nitrogen fixing enzyme activity was 4 folds higher and chlorophyll content was 21.3% higher in the ARC-BBBE treated group compared to the control group. The results of soybean potted planting experiment in greenhouse revealed that ARC-BBBE also promoted nodulation and nitrogen fixation in soybean, with a 13.5-fold increase in the number of nodules and a 19.8-fold increase in nodule weight in the ARC-BBBE-treated group compared to the control group. At 26 days after sowing, the root nodules in the treatment group had nitrogen fixation activity while those in the control group had no activity, and biological indices such as root length, root weight, fresh weight and chlorophyll level were significantly enhanced in the treatment group. The effect of ARC-BBBE on the control of Aspergillus flavus and its toxin in peanut is extremely obvious. ARC-BBBE does not only effectively inhibit peanut aflatoxin-producing fungi and reduce the risk of aflatoxin contamination from the source of production, but also significantly improves the amount of peanut root nodules and nitrogen-fixing enzyme activity, which is of remarkable growth-promoting, yield-increasing, disease-control, safety-preserving properties, and economic, social and ecological benefits. Thus, it is of great significance in minimizing the application of pesticides and fertilizers, protecting farmland ecology, and promoting the high-quality environment-friendly development of the peanut industry, which is prospective for application in the production of peanut, soybean and other leguminous crops in the future.