The textile industry is one of those industries that discharges great amounts of effluents with synthetic dyes into the environment, causing public concern. This study focuses on the effectiveness of Ethiopian kaolin, a naturally abundant clay mineral, in adsorbing methylene blue dye from aqueous solutions, particularly in textile wastewater treatment.The kaolin adsorbents (raw powder, beneficiated, acid leached, and calcined) were prepared from Ethiopian natural kaolin through mechanical, wet, chemical, and thermal processes.The research aims to compare the adsorption capacities of various forms of kaolin, including raw (RK), beneficiated (BK), acid-leached (ALK), and calcined (CK) under different operational parameters such as temperature, pH, adsorbent dosage, contact time, and dye concentration through batch adsorption experiments.The study utilized characterization techniques like XRD, FTIR, BET, and UV-Vis spectrometry to analyze the adsorbents well. Adsorption experiments were carried out in batch mode to study the effects of adsorbent dosages (0.2-1 g), pH (3-11), initial concentrations of MB (20 to 100 mg/L), contact time (20 to 100 min), and temperature (30 to 70 °C). For raw, beneficiated, calcined, and acid-leached kaolin adsorbent, the highest methylene blue dye removal efficiency was found to be 99%, 99.84%, 99.76%, and 100%, respectively, at an initial concentration of 20 mg/L, temperature of 30 °C, contact time of 60 minutes, solution pH of 9, and adsorbent dose of 1 g/100 ml. Meanwhile, the equilibrium condition could be reached with 20 mg/L, a temperature below 30°C, contact times of 60 minutes for ALK and BK and 40 minutes for CK and RK, a solution pH of 9, and an adsorbent dosage of 1 g/100 mL. These results also revealed that the process was more efficient at temperatures of 30 °C. This suggests that the thermodynamic behavior at the lowest temperature is more feasible and spontaneous than at higher temperatures, and the process was exothermic. This study has revealed that both raw and modified Ethiopian kaolin have good adsorption efficiency because all adsorbents have greater than 90% removal efficiency. Even more than 90% removal efficiency was observed after five reuse cycles, proving the stability and reusability of the adsorbents. Therefore, these adsorbents are considered ideal for the removal of methylene blue dyes from polluted water. Moreover, acid activation resulted in a more effective adsorbent than thermal and wet treatment.