The effect of addition of sodium dodecyl sulfate (SDS) anionic surfactant on the characteristics and performance (i.e. flux and rejection) of cellulose acetate (CA) nanofiltration membrane was investigated at this study. Nitrophenols (p-nitrophenol (PNP) and 3,5-dinitrosalicylic acid (DNSA)) were selected as the subject-matter of this study since they are listed as two of the harmful pesticides in drinking water by US Environmental Protection Agency. The prepared membranes were characterized by several techniques including SEM, AFM, FTIR-ATR, water contact angle, and zeta potential measurements. The process of addition of SDS resulted in membranes with higher pure water flux, superior rejection, and flux in comparison to CA membrane. Also, it was found that the rejection of PNP and DNSA depend on a series of factors including the solution pH, structural properties of the solutes, and characteristics of the membranes. (C) 2012 Elsevier B.V. All rights reserved.