The present work was conducted to investigate the kinetics of cobalt removal from aqueous solutions using a Flow-by fixed bed bio-electrochemical reactor. Effects of process parameters namely applied voltage, Initial cobalt concentration, and pH on the reaction rate constant (k) were investigated. The results shows that the cathodic deposition was occurred under mass transfer control for all values of the applied voltage used in this research. Accordingly, the relation between concentration and time can be represented by a first order equation. The rate constant was found to be dependent on the applied voltage, initial cobalt concentration and pH. It was increased as the applied voltage increased and decreased as the initial concentration increased. The dependency of rate constant on the applied voltage was found to an exponential form similar to Arrhenius form. pH has two dissimilar effects on the rate constant, its increasing from 3-7 leads to an increase in the rate constant while at alkaline condition ,the rate constant was found to be decreased.