A comparative study of several organic compounds (atrazine, aniline and phenol, and their derivatives, 4-chlorophenol, 4-nitrophenol and 4-nitroaniline) and their removal from aqueous solutions by nanofiltration using an NF-97 polyamide membrane is presented. The aim was to ascertain any correlation between the physicochemical parameters of the different compounds and the characteristic parameters of the nanofiltration system (permeate flux and rejection coefficient), in order to understand the behavior of the nanofiltration membrane separation processes and any relevant variables. In a previous work, the rejection coefficients and permeate flux values for phenol, 4-chlorophenol, aniline, and atrazine were obtained. These values were used together with the new ones presented for 4-nitroaniline and 4-nitrophenol.