Removal of nitrate from water was studied using the surfactant-enhanced crossflow filtration (SECF) technique with the cationic surfactant, hexadeclytrimethylammoniumbromide (CTAB). The variation of nitrate and surfactant rejections and permeate flux with time were measured as a function of CTAB/nitrate ratio, transmembrane pressure drop (Delta P), membrane pore size, pH of the feed solution, and electrolyte (NaCl) concentration. The method was found to be effective in removing nitrate from water. It was observed that the efficiency of nitrate removal increased with increasing CTAB/nitrate ratio. Nitrate and CTAB rejections decreased with increasing electrolyte concentration, while pH did not have any significant direct effect on rejection. The pseudo-gel concentration (C-g(*)) determined from the linear portion of steady-state permeate flux versus log (C-SF) was 18 gl(-1), where C-SF is the surfactant feed concentration. It was observed that even when C-SF was greater then C-g(*) there was a certain amount of permeate flux. The efficiency of the process was shown to be higher for larger membrane pore size.