Land with low pH soil spread widely in Indonesia can be used for soybean (Glycine max) cultivation, although the production is low. The use of acid tolerant soybean and acid-Al tolerant nitrogen-fixing bacteria was an alternative way to increase soybean productivity on acid soils. This research was conducted to study the influence of acid-Al tolerant Bradyrhizobium japonicum on growth of Slamet cultivar soybean planted on acid soils in greenhouse. Three strains of acid-Al tolerant B. japonicum, i.e. BJ 11 (19), BJ 11 (5), and BJ 11 (wt), were used in this experiment. The result showed that inoculation of all acid-Al tolerant B. japonicum strains could increase plant height, shoot and root weight, number of flowers, pods, seeds, seeds dry weight, and shoot and seed nitrogen content.
