The effect of pulsed flow on mass transfer in an electrolytic reactor was investigated using carbon felt electrode arranged in a way that the electrolyte and the current flows were parallel to each other. In these experiments, a solution of potassium ferri- and ferro-cyanide with inactive compound of sodium hydroxide was employed. The electrolyte superficial velocity was in the range 4.29 x 10(-4)-18.2 x 10(-4) m s(-1). The frequency and the normalised amplitude of the pulse in the flow rate were changed in the range 0.17-3.55 s(-1) and 3.5 x 10(-3)-1.0 x 10(-2) m, respectively. The experiments showed that the pulsed flow increased significantly the transfer of reacting ions onto the electrode surface up to a frequency of 1.5 s(-1) and over this frequency the current ratio was effected slightly with increasing frequency. The increasing amplitude also had a positive effect on transfer rate, but not as pronounced as the frequency. An increase in the mass transfer rate between approximately 6.8 and 33.5 times of those of the flow with no pulse was obtained, depending upon the experimental conditions.