Pollution of industrial effluents including oily wastewaters having organic toxic compounds such as phenol, is one of the most important environmental issues. There are many processes to remove the phenolic compounds which are mostly expensive and less efficient. In this regard, adsorption by a low cost carbonaceous adsorbent is one of the efficient and cost-effective approaches. In this study, the biological sludge of Tehran oil refinery wastewater unit was used for production of activated carbon and removal of phenol. The biological sludge was activated after carbonization using various chemical and physical methods. After adsorption tests of samples, the sample activated with steam at 950° c was chosen for the next experiments. Some characteristics of the produced activated carbon including concentration of heavy metals, leaching tests, Fourier Transform Infrared Spectroscopy (FT-IR), specific surface area (using BET method) and scanning electron microscope (SEM) were determined. The specific surface area of the carbonized and activated carbon samples were 10.4 and 86.2 m 2 /g, respectively. Besides, the images obtained by SEM showed an increase in the number of pores in the produced activated carbon. Adsorption tests were done by evaluating the effect of the four factors including the adsorbent amount, initial phenol concentration, pH and contact time in four levels using Taguchi method. The maximum adsorption amount of phenol in optimum conditions was 96.2 %. Results showed that amount of the adsorbent and contact time have the most influence on phenol adsorption. Furthermore, kinetic models of phenol adsorption on produced activated carbon showed that the pseudo-first order model was better fit adsorption data in comparison to the models of pseudo–second order, Elvich and interparticle defusion. Fitting the results with the isotherm models of Langmuir, Freundlich, Redlich- Peterson and Temkin indicated that the phenol adsorption using the produced activated carbon was more followed by Redlich-Peterson model. In the column tests, the highest amount of adsorption and desorption were 21 and 45 %, respectively. Phenol efficiency of produced activated carbon in wastewater samples of oil refinery was 73 %. Overall, based on the obtained results, the produced activated carbon showed an efficient ability for removal of phenol from aqueous solutions. Keywords : Adsorption, Phenol, Activated carbon, Biological sludge