As one solid waste with potential for phosphorus removal, application of slags in water treatment merits attention. But it was inhibited greatly by alkaline solution ( pH > 9.5) and cemented clogging generated. To give one solution, phosphorus removal was investigated by combining deep-sea bacterium Alteromonas 522-1 and basic oxygen furnace slag (BOFS). Results showed that by the combination, not only higher phosphorous removal efficiency (>90%) but also neutral solution pH of 7.8-8.0 were achieved at wide ranges of initial solution pH value of 5.0-9.0, phosphorus concentration of 5-30 mg/L, salinity of 0.5-3.5%, and temperature of 15-35 degrees C. Moreover, sedimentary property was also improved with lower amount of sludge production and alleviated BOFS cementation with increased porosity and enlarged particle size. These results provided a promising strategy for the phosphorus recovery with slags in large-scale wastewater treatment. (C) 2016 Elsevier Ltd. All rights reserved.