The influence of certain surfactants on the dewatering of fine iron ore sludge flocculated with anionic flocculants has been investigated in a laboratory-scale vacuum filtration unit. The filtration data have been used in calculating the cake parameters from an integrated form of Darcy's lau. A narrow concentration range of surfactant enables reduction of the specific cake resistance and an enhanced rate of filtration. The non-ionic surfactant polyethylene oxide (PEO) was most effective in reducing the moisture content of the cake. Filter cake with 12.6% moisture content has been obtained using this surfactant. The surface tension reduction mechanism is responsible to some extent for the enhanced dewatering, but does not account for all the effects. A complex surfactant adsorption mechanism in the presence of flocculants seems to play a greater role in enhancing dewatering.