Seafood processing operations generate a high strength wastewater, which contain organic pollutants in soluble, colloidal, particulate form and salt content, up to 30g NaCl/L. This research aimed to study the effect of salt (NaCl) concentration on the treatment efficiency of seafood processing wastewater by the use of a laboratory-scale bioreactor, which is operated in anaerobic combining aerobic system with concentration salt different from 0- 5%. The results showed that the wastewater from seafood processing with the chemical input parameters of pH = 7 - 8.5, COD = 2000 mg / L, total nitrate nitrogen = 150 mg / L, NH⁴⁺ = 90 mg / L, total phosphorus = 50 mg / L, salt content 3% was treated with anaerobic activated sludge content of 8000mg/l, 16HRT and combining an aerobic activated sludge content of 6000mg/l, 6HRT, DO=2-4mgO₂/l with the acclimatization of 7% bacteria Bacillus velezensis at high salinity The parameters output wastewater was treated according to standards QCVN 11-MT:2015/BTNMT (column B).