The aim of this work was to study the removal of methylene blue (MB) and phenol from aqueous solution using powder activated carbon prepared from cola nut shells chemically activated with KOH solution. The effect of contact time, adsorbent dose, pH and initial concentration has been studied using batch adsorption method. Given the base line for the results, the percentage removal of MB and phenol were 98.19 % and 61.81 % respectively. The maximum adsorption of MB and phenol occur at pH 8 and 6. Also the quantity adsorbed decreases with the adsorbent dose for both adsorbates. The quantity adsorbed of MB increases with increased in initial concentration whereas reverse result was observed with phenol. The adsorption equilibrium data were confronted to Langmuir, Freundlich, Tempkin and Dubinin-Kaganer-Radushkevich isotherms models. The Langmuir model describes better the adsorption with maximum monolayer adsorption capacities of 65.79 mg.g-1 and 6.22 mg.g-1 for MB and phenol respectively. The kinetics of methylene blue and phenol adsorption were also discussed using pseudo-first-order, pseudo-second-order, Elovich, mass transfer and intra-particle diffusion models. The adsorption process follows the pseudosecond- order and mass transfer kinetic models respectively for methylene blue and phenol owing to their high correlation coefficient. This study shows that the prepared activated carbon can be used as low cost alternative adsorbent for removal of both phenol and MB.