The use of sewage sludge activated carbon (thickened samples ACS1 and non-thickened samples ACS2) in a variety of applications and simple and environmentally friendly pro-duction techniques are attracting more and more attention. We offer here a novel environ-mentally friendly method based on the green synthesis of activated carbons (ACS1 / ACS2) using sewage sludge (SS). These activated carbons are then used to effectively remove the water-based reactive dye phenol red (PR). The ACS1 and ACS2 produced are porous mate-rials with an average diameter of 20.72 – 13.30 and 6.20 – 7.34nm, respectively. These ACS1/ACS2 were analyzed using a range of characterization techniques including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron mi-croscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) analysis. Elimination of toxic PR dye was investigated using several operational factors, including ACS1/ACS2 dose, initial PR dye concentration, pH and temperature. Under the best experimental conditions, the ACS1 and ACS2 adsorbents absorbed nearly 89.58% and 97.69% of the PR dye, respectively. It was found that both ACS1 and ACS2 adsorption corresponded to pseudo-first order kinetics (R = 0.996 and 0.980) and fulfilled Langmuir’s (ACS1) and Freundlich’s (ACS2) models well, with maximum adsorption ca-pacities of 65.35 and 122.72 mg/g, respectively. It was found that the adsorption processes are basically exothermic. The results suggest that sewage sludge can be effective as a low-cost and environmentally benefit synthesis of ACS1 and ACS2 in the purification of water sources contaminated with hazardous dyes.