A new type of forward osmosis (FO) hollow fiber membranes with an antifouling nanofiltration (NF)-like selective layer has been developed in this work. The fabrication involves a step of porous poly(amide-imide) (PAI) ultrafiltration (UF) hollow fiber spinning via phase inversion, followed by simple polyelectrolyte post-treatments using positively charged polyethyleneimine (PEI) for cross-linking and negatively charged polystyrene sulfonate sodium salt (PSS) for deposition.The membranes are subsequently characterized by a series of standard protocols and evaluated in FO process. The PAI FO membranes possess a pure water permeability of 3.7–4.3Lm −2 h −1 bar −1 and Na 2 SO 4 rejections up to 85% at 1bar. In the FO process, the membranes can achieve water flux of 17 and 12Lm −2 h −1 for active layer facing draw solution (AL-facing-DS) and active layer facing feed water (AL-facing-FW) configurations, respectively, using a 2000ppm Na 2 SO 4 aqueous solution as the feed and 0.5M Na 2 SO 4 as the draw solution. When the feed contained 1000ppm bovine serum albumin (BSA) and 2000ppm Na 2 SO 4 , a steady water flux of 11Lm −2 h −1 can be maintained using 0.5M Na 2 SO 4 as the draw solution at ambient temperature of 23°C. The approach of making FO membranes developed in the present study offers the advantages of simple fabrication process, tailorable selective layer and promising membrane performance for protein-contained wastewater treatment by FO process.