In this study, the results of nanofiltration experiments carried out on reactive dye house wastewaters are presented. The experiments were performed using lab-scale membrane system. Permeate quality was appropriate to reuse permeate in dyeing process again. Pretreatment and neutralization were the parameters which are very important for the recovery of high amounts of salt and water at the permeate stream. In addition, use of HCl instead of H2SO4 for neutralization increased the NaCl recovery.